POST-EFFECTIVE AMENDMENT NO. 120

485BPOS 1 pea120-2007.htm POST-EFFECTIVE AMENDMENT NO. 120 POST-EFFECTIVE AMENDMENT NO. 120


                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                    FORM N-1A

REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933              [X]

     File No. 2-14213

     Pre-Effective Amendment No.                                     [ ]

     Post-Effective Amendment No. 120                                [X]

                             and/or

REGISTRATION STATEMENT UNDER THE INVESTMENT COMPANY ACT OF 1940      [X]

     File No. 811-0816

     Amendment No. 120                                               [X]

                     (Check appropriate box or boxes.)


                       AMERICAN CENTURY MUTUAL FUNDS, INC.
--------------------------------------------------------------------------------
               (Exact Name of Registrant as Specified in Charter)


                     4500 MAIN STREET, KANSAS CITY, MO 64111
--------------------------------------------------------------------------------
               (Address of Principal Executive Offices) (Zip Code)


   Registrant's Telephone Number, including Area Code: (816) 531-5575


         CHARLES A. ETHERINGTON, 4500 MAIN STREET, KANSAS CITY, MO 64111
--------------------------------------------------------------------------------
                     (Name and Address of Agent for Service)

           Approximate Date of Proposed Public Offering: March 1, 2007

It is proposed that this filing will become effective (check appropriate box)

     [ ] immediately upon filing pursuant to paragraph (b)
     [X] on March 1, 2007, pursuant to paragraph (b)
     [ ] 60 days after filing pursuant to paragraph (a)(1)
     [ ] on (date) pursuant to paragraph (a)(1)
     [ ] 75 days after filing pursuant to paragraph (a)(2)
     [ ] on (date) pursuant to paragraph (a)(2) of rule 485.

If appropriate, check the following box:

     [ ] This post-effective amendment designates a new effective date for a
         previously filed post-effective amendment.






AMERICAN CENTURY INVESTMENTS

Prospectus

March 1, 2007

Ultra® Fund

THE SECURITIES AND EXCHANGE COMMISSION HAS NOT APPROVED OR DISAPPROVED THESE
SECURITIES OR PASSED UPON THE ADEQUACY OF THIS PROSPECTUS. ANY REPRESENTATION TO
THE CONTRARY IS A CRIMINAL OFFENSE.

American Century Investment Services, Inc., Distributor

[american century investments logo and text logo]





Table of Contents

AN OVERVIEW OF THE FUND . . . . . . . . . . . . . . . . . . . . . . . . . . . .2

FUND PERFORMANCE HISTORY . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

FEES AND EXPENSES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6

OBJECTIVES, STRATEGIES AND RISKS . . . . . . . . . . . . . . . . . . . . . . . 8

MANAGEMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10

INVESTING DIRECTLY WITH AMERICAN CENTURY . . . . . . . . . . . . . . . . . . .12

INVESTING THROUGH A FINANCIAL INTERMEDIARY . . . . . . . . . . . . . . . . . .14

ADDITIONAL POLICIES AFFECTING YOUR INVESTMENT . . . . . . . . . . . . . . . . 16

SHARE PRICE AND DISTRIBUTIONS . . . . . . . . . . . . . . . . . . . . . . . . 20

TAXES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

MULTIPLE CLASS INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . .24

FINANCIAL HIGHLIGHTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25

        [graphic of triangle]

        THIS SYMBOL IS USED THROUGHOUT THE BOOK TO HIGHLIGHT
        DEFINITIONS OF KEY INVESTMENT TERMS AND TO PROVIDE
        OTHER HELPFUL INFORMATION.


American Century Investment Services, Inc., Distributor

©2007 American Century Proprietary Holdings, Inc. All rights reserved.

The American Century Investments logo, American Century and American Century
Investments are service marks of American Century Proprietary Holdings, Inc.




AN OVERVIEW OF THE FUND

WHAT IS THE FUND'S INVESTMENT OBJECTIVE?

The fund seeks long-term capital growth.

WHAT ARE THE FUND'S PRIMARY INVESTMENT STRATEGIES AND PRINCIPAL RISKS?

The portfolio managers look for stocks of companies they believe will increase
in value over time, using investment strategies developed by American Century.
In implementing these strategies, the portfolio managers make their investment
decisions based primarily on their analysis of individual companies, rather than
on broad economic forecasts. Management of the fund is based on the belief that,
over the long term, stock price movements follow growth in earnings, revenues
and/or cash flow.

The portfolio managers use a variety of analytical research tools and techniques
to identify the stocks of larger-sized companies that meet their investment
criteria. Under normal market conditions, the fund's portfolio will primarily
consist of securities of companies whose earnings or revenues are not only
growing, but growing at an accelerating pace.

The fund's principal risks include

*  GROWTH STOCKS - Investments in growth stocks may involve special risks and
   their prices may fluctuate more dramatically than the overall stock market.

*  FOREIGN SECURITIES - A fund may invest in foreign securities, which can be
   riskier than investing in U.S. securities.

*  MARKET RISK - The value of a fund's shares will go up and down based on
   the performance of the companies whose securities it owns and other factors
   generally affecting the securities market.

*  PRICE VOLATILITY - The value of a fund's shares may fluctuate
   significantly in the short term.

*  PRINCIPAL LOSS - At any given time your shares may be worth less than the
   price you paid for them. In other words, it is possible to lose money by
   investing in the fund.

A more detailed description of the fund's investment strategies and risks may be
found under the heading OBJECTIVES, STRATEGIES AND RISKS which begins on page 8.

        [graphic of triangle]

        AN INVESTMENT IN THE FUND IS NOT A BANK DEPOSIT, AND IT IS NOT INSURED
        OR GUARANTEED BY THE FEDERAL DEPOSIT INSURANCE CORPORATION (FDIC) OR ANY
        OTHER GOVERNMENT AGENCY.


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2


FUND PERFORMANCE HISTORY

Annual Total Returns

The following bar chart shows the performance of the fund's Investor Class
shares for each of the last 10 calendar years. It indicates the volatility of
the fund's historical returns from year to year. Account fees and sales charges,
if applicable, are not reflected in the chart below. If they had been included,
returns would be lower than those shown. The returns of the fund's other classes
will differ from those shown in the chart, depending on the expenses of those
classes.

ULTRA FUND - INVESTOR CLASS

The highest and lowest quarterly returns for the periods reflected in the bar
chart are:

HIGHEST LOWEST
--------------------------------------------------------------------------------
Ultra 32.09% (4Q 1999) -17.49% (1Q 2001)
--------------------------------------------------------------------------------

Average Annual Total Returns

The following table shows the average annual total returns of the fund's
Investor Class shares calculated three different ways. Additional tables show
the average annual total returns of the fund's other share classes calculated
before the impact of taxes. Returns assume the deduction of all sales loads,
charges and other fees associated with a particular class. Your actual returns
may vary depending on the circumstances of your investment.

Return Before Taxes shows the actual change in the value of fund shares over the
time periods shown, but does not reflect the impact of taxes on fund
distributions or the sale of fund shares. The two after-tax returns take into
account taxes that may be associated with owning fund shares. Return After Taxes
on Distributions is a fund's actual performance, adjusted by the effect of taxes
on distributions made by the fund during the periods shown. Return After Taxes
on Distributions and Sale of Fund Shares is further adjusted to reflect the tax
impact on any change in the value of fund shares as if they had been sold on the
last day of the period.

After-tax returns are calculated using the historical highest federal marginal
income tax rates and do not reflect the impact of state and local taxes. Actual
after-tax returns depend on an investor's tax situation and may differ from
those shown. After-tax returns shown are not relevant to investors who hold fund
shares through tax-deferred arrangements such as 401(k) plans or IRAs. After-tax
returns are shown only for the Investor Class shares. After-tax returns for the
other share classes will vary.

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3

The benchmarks are unmanaged indices that have no operating costs and are
included in each table for performance comparison.

INSTITUTIONAL CLASS
FOR THE CALENDAR YEAR ENDED DECEMBER 31, 2006 1 YEAR 5 YEARS 10 YEARS
--------------------------------------------------------------------------------
Return Before Taxes -3.08% 1.32% 5.62%
Russell 1000® Growth Index 9.07% 2.69% 5.44%
(reflects no deduction
for fees, expenses or taxes)
S&P 500® Index 15.79% 6.19% 8.42%
(reflects no deduction
for fees, expenses or taxes)
--------------------------------------------------------------------------------

C CLASS
LIFE OF
FOR THE CALENDAR YEAR ENDED DECEMBER 31, 2006 1 YEAR 5 YEARS CLASS(1)
--------------------------------------------------------------------------------
Return Before Taxes -4.24% 0.11% 1.63%
Russell 1000® Growth Index 9.07% 2.69% 3.48%(2)
(reflects no deduction
for fees, expenses or taxes)
S&P 500® Index 15.79% 6.19% 6.90%(2)
(reflects no deduction
for fees, expenses or taxes)
--------------------------------------------------------------------------------

(1) THE INCEPTION DATE FOR THE C CLASS IS OCTOBER 29, 2001. ONLY CLASSES
WITH PERFORMANCE HISTORY FOR LESS THAN 10 YEARS SHOW RETURNS FOR LIFE OF
CLASS.

(2) SINCE OCTOBER 25, 2001, THE DATE CLOSEST TO THE CLASS'S INCEPTION FOR
WHICH DATA IS AVAILABLE.

R CLASS
LIFE OF
FOR THE CALENDAR YEAR ENDED DECEMBER 31, 2006 1 YEAR CLASS(1)
--------------------------------------------------------------------------------
Return Before Taxes -3.75% 4.35%
Russell 1000® Growth Index 9.07% 9.01%(2)
(reflects no deduction
for fees, expenses or taxes)
S&P 500® Index 15.79% 12.82%(2)
(reflects no deduction
for fees, expenses or taxes)
--------------------------------------------------------------------------------

(1) THE INCEPTION DATE FOR THE R CLASS IS AUGUST 29, 2003. ONLY CLASSES
WITH PERFORMANCE HISTORY FOR LESS THAN 10 YEARS SHOW RETURNS FOR LIFE OF
CLASS.

(2) SINCE AUGUST 31, 2003, THE DATE CLOSEST TO THE CLASS'S INCEPTION FOR
WHICH DATA IS AVAILABLE.

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4

ADVISOR CLASS
FOR THE CALENDAR YEAR ENDED DECEMBER 31, 2006 1 YEAR 5 YEARS 10 YEARS
--------------------------------------------------------------------------------
Return Before Taxes -3.50% 0.86% 5.16%
Russell 1000® Growth Index 9.07% 2.69% 5.44%
(reflects no deduction
for fees, expenses or taxes)
S&P 500® Index 15.79% 6.19% 8.42%
(reflects no deduction
for fees, expenses or taxes)
--------------------------------------------------------------------------------

Performance information is designed to help you see how fund returns can vary.
Keep in mind that past performance (before and after taxes) does not predict how
the fund will perform in the future.

For current performance information, please call us or visit
americancentury.com.

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5

FEES AND EXPENSES

There are no sales loads, fees or other charges

* to buy fund shares directly from American Century

* to reinvest dividends in additional shares

* to exchange into the same class of shares of other American Century funds

* to redeem your shares (other than a $10 fee to redeem by wire and the
deferred sales charge associated with C Class shares redeemed during the
first year after purchase)

The following tables describe the fees and expenses you may pay if you buy and
hold shares of the fund.

SHAREHOLDER FEES (FEES PAID DIRECTLY FROM YOUR INVESTMENT)
--------------------------------------------------------------------------------
Investor Class
Maximum $25(1)
Account
Maintenance
Fee
--------------------------------------------------------------------------------
C Class
Maximum 1.00%(2)
Deferred Sales
Charge (load)
(as a
percentage
of net asset
value)
--------------------------------------------------------------------------------

(1) APPLIES ONLY TO INVESTORS WHOSE TOTAL ELIGIBLE INVESTMENTS WITH
AMERICAN CENTURY ARE LESS THAN $10,000. SEE Account Maintenance Fee UNDER
Investing Directly with American Century FOR MORE DETAILS.

(2) THE DEFERRED SALES CHARGE IS CONTINGENT ON THE LENGTH OF TIME YOU HAVE
OWNED YOUR SHARES. THE CHARGE IS 1.00% DURING THE FIRST YEAR AFTER PURCHASE
AND IS ELIMINATED THEREAFTER.

ANNUAL FUND OPERATING EXPENSES (EXPENSES THAT ARE DEDUCTED FROM FUND ASSETS)
DISTRIBUTION TOTAL ANNUAL
MANAGEMENT AND SERVICE OTHER FUND OPERATING
FEE(1) (12B-1) FEES(2) EXPENSES(3) EXPENSES
--------------------------------------------------------------------------------
Investor 0.99% None 0.00% 0.99%
Class
--------------------------------------------------------------------------------
Institutional 0.79% None 0.00% 0.79%
Class
--------------------------------------------------------------------------------
C Class 0.99% 1.00% 0.00% 1.99%
--------------------------------------------------------------------------------
R Class 0.99% 0.50% 0.00% 1.49%
--------------------------------------------------------------------------------
Advisor 0.74% 0.50% 0.00% 1.24%
Class
--------------------------------------------------------------------------------

(1) THE FUND PAYS THE ADVISOR A SINGLE, UNIFIED MANAGEMENT FEE FOR
ARRANGING ALL SERVICES NECESSARY FOR THE FUND TO OPERATE. THE FEE SHOWN IS
BASED ON ASSETS DURING THE FUND'S MOST RECENT FISCAL YEAR. THE FUND HAS A
STEPPED FEE SCHEDULE. AS A RESULT, THE FUND'S UNIFIED MANAGEMENT FEE RATE
GENERALLY DECREASES AS STRATEGY ASSETS INCREASE AND INCREASES AS STRATEGY
ASSETS DECREASE. FOR MORE INFORMATION ABOUT THE UNIFIED MANAGEMENT FEE,
INCLUDING AN EXPLANATION OF STRATEGY ASSETS, SEE The Investment Advisor
UNDER Management.

(2) THE 12B-1 FEE IS DESIGNED TO PERMIT INVESTORS TO PURCHASE SHARES
THROUGH BROKER-DEALERS, BANKS, INSURANCE COMPANIES AND OTHER FINANCIAL
INTERMEDIARIES. THE FEE MAY BE USED TO COMPENSATE SUCH FINANCIAL
INTERMEDIARIES FOR DISTRIBUTION AND OTHER SHAREHOLDER SERVICES. IN
ADDITION, HALF OF THE ADVISOR CLASS 12B-1 FEE (0.25%) IS FOR ONGOING
RECORDKEEPING AND ADMINISTRATIVE SERVICES PROVIDED BY FINANCIAL
INTERMEDIARIES, WHICH WOULD OTHERWISE BE PAID BY THE ADVISOR OUT OF THE
UNIFIED MANAGEMENT FEE. THE ADVISOR HAS REDUCED ITS UNIFIED MANAGEMENT FEE
BY 0.25% FOR ADVISOR CLASS SHARES, BUT THE FEE FOR CORE INVESTMENT ADVISORY
SERVICES IS THE SAME FOR ALL CLASSES. FOR MORE INFORMATION, SEE Multiple
Class Information AND Service, Distribution and Administrative Fees, PAGE
24.

(3) OTHER EXPENSES, WHICH INCLUDE THE FEES AND EXPENSES OF THE FUND'S
INDEPENDENT DIRECTORS AND THEIR LEGAL COUNSEL, INTEREST, AND FEES AND
EXPENSES INCURRED INDIRECTLY BY THE FUND AS A RESULT OF INVESTMENT IN
SHARES OF ONE OR MORE MUTUAL FUNDS, HEDGE FUNDS, PRIVATE EQUITY FUNDS OR
OTHER POOLED INVESTMENT VEHICLES, WERE LESS THAN 0.005% FOR THE MOST RECENT
FISCAL YEAR.

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6

EXAMPLE

The examples in the table below are intended to help you compare the costs of
investing in the fund with the costs of investing in other mutual funds. Of
course, your actual costs may be higher or lower. Assuming you . . .

* invest $10,000 in the fund

* redeem all of your shares at the end of the periods shown below

* earn a 5% return each year

* incur the same operating expenses as shown above

. . . your cost of investing in the fund would be:

1 YEAR 3 YEARS 5 YEARS 10 YEARS
--------------------------------------------------------------------------------
Investor Class $101 $314 $545 $1,208
--------------------------------------------------------------------------------
Institutional Class $81 $252 $438 $975
--------------------------------------------------------------------------------
C Class $201 $620 $1,064 $2,295
--------------------------------------------------------------------------------
R Class $151 $469 $809 $1,767
--------------------------------------------------------------------------------
Advisor Class $126 $392 $678 $1,492
--------------------------------------------------------------------------------

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7

OBJECTIVES, STRATEGIES AND RISKS

WHAT IS THE FUND'S INVESTMENT OBJECTIVE?

The fund seeks long-term capital growth.

HOW DOES THE FUND PURSUE ITS INVESTMENT OBJECTIVE?

The portfolio managers look for stocks of larger-sized companies they believe
will increase in value over time, using an investment strategy developed by
American Century. In implementing this strategy, the portfolio managers use a
bottom-up approach to stock selection. This means that the portfolio managers
make their investment decisions based primarily on their analysis of individual
companies, rather than on broad economic forecasts. Management of the fund is
based on the belief that, over the long term, stock price movements follow
growth in earnings, revenues and/or cash flow.

Using American Century's extensive computer database, as well as other primary
analytical research tools, the portfolio managers track financial information
for individual companies to identify and evaluate trends in earnings, revenues
and other business fundamentals. Under normal market conditions, the fund's
portfolio will primarily consist of securities of companies whose earnings and
revenues are not only growing, but growing at an accelerating pace. This
includes companies whose growth rates, although still negative, are less
negative than prior periods, and companies whose growth rates are expected to
accelerate. Other analytical techniques help identify additional signs of
business improvement, such as increasing cash flows, or other indications of the
relative strength of a company's business. In addition to accelerating growth
and other signs of business improvement, the fund also considers companies
demonstrating price strength relative to their peers. These techniques help the
portfolio managers buy or hold the stocks of companies they believe have
favorable growth prospects and sell the stocks of companies whose
characteristics no longer meet their criteria.

Although the portfolio managers intend to invest the fund's assets primarily in
U.S. stocks, the fund may invest in securities of foreign companies, including
companies located in emerging markets. Investments in foreign securities present
some unique risks that are more fully described in the fund's statement of
additional information.

The portfolio managers do not attempt to time the market. Instead, under normal
market conditions, they intend to keep the fund essentially fully invested in
stocks regardless of the movement of stock prices generally. When the managers
believe it is prudent, the fund may invest a portion of its assets in debt
securities, options, preferred stock and equity-equivalent securities, such as
convertible securities, stock futures contracts or stock index futures
contracts. The fund generally limits its purchase of debt securities to
investment-grade obligations. Futures contracts, a type of derivative security,
can help the fund's cash assets remain liquid while performing more like stocks.
The fund has a policy governing futures contracts and similar derivative
securities to help manage the risk of these types of investments. A complete
description of the derivatives policy is included in the statement of additional
information.

In the event of exceptional market or economic conditions, the fund may, as a
temporary defensive measure, invest all or a substantial portion of its assets
in cash, cash-equivalent securities or short-term debt securities. To the extent
the fund assumes a defensive position it will not be pursuing its objective of
long-term capital growth.

A description of the policies and procedures with respect to the disclosure of
the fund's portfolio securities is available in the statement of additional
information.

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8

WHAT ARE THE PRINCIPAL RISKS OF INVESTING IN THE FUND?

Growth stocks are typically priced higher than other stocks, in relation to
earnings and other measures, because investors believe they have more growth
potential. This potential may or may not be realized and growth stock prices
tend to fluctuate more dramatically than the overall stock market.

The portfolio managers may buy a large amount of a company's stock quickly, and
often will dispose of it quickly if the company's earnings or revenues decline.
While the managers believe this strategy provides substantial appreciation
potential over the long term, in the short term it can create a significant
amount of share price volatility. This volatility can be greater than that of
the average stock fund.

Although the portfolio managers intend to invest the fund's assets primarily in
U.S. stocks, the fund may invest in securities of foreign companies. Foreign
investment involves additional risks, including fluctuations in currency
exchange rates, less stable political and economic structures, reduced
availability of public information, and lack of uniform financial reporting and
regulatory practices similar to those that apply in the United States. These
factors make investing in foreign securities generally riskier than investing in
U.S. stocks. To the extent a fund invests in foreign securities, the overall
risk of that fund could be affected.

Market performance tends to be cyclical, and, in the various cycles, certain
investment styles may fall in and out of favor. If the market is not favoring a
fund's style, the fund's gains may not be as big as, or its losses may be bigger
than, other equity funds using different investment styles.

The value of a fund's shares depends on the value of the stocks and other
securities it owns. The value of the individual securities a fund owns will go
up and down depending on the performance of the companies that issued them,
general market and economic conditions, and investor confidence.

At any given time your shares may be worth less than the price you paid for
them. In other words, it is possible to lose money by investing in the fund.

------
9

MANAGEMENT

WHO MANAGES THE FUND?

The Board of Directors, investment advisor and fund management team play key
roles in the management of the fund.

THE BOARD OF DIRECTORS

The Board of Directors oversees the management of the fund and meets at least
quarterly to review reports about fund operations. Although the Board of
Directors does not manage the fund, it has hired an investment advisor to do so.
More than three-fourths of the directors are independent of the fund's advisor;
that is, they have never been employed by and have no financial interest in the
advisor or any of its affiliated companies (other than as shareholders of
American Century funds).

THE INVESTMENT ADVISOR

The fund's investment advisor is American Century Investment Management, Inc.
(the advisor). The advisor has been managing mutual funds since 1958 and is
headquartered at 4500 Main Street, Kansas City, Missouri 64111.

The advisor is responsible for managing the investment portfolios of the fund
and directing the purchase and sale of their investment securities. The advisor
also arranges for transfer agency, custody and all other services necessary for
the fund to operate.

For the services it provides to the fund, the advisor receives a unified
management fee based on a percentage of the daily net assets of each class of
shares of the fund. The amount of the fee is calculated daily and paid monthly
in arrears. Out of that fee, the advisor pays all expenses of managing and
operating the fund except brokerage expenses, taxes, interest, fees and expenses
of the independent directors (including legal counsel fees), and extraordinary
expenses. A portion of the fund's management fee may be paid by the fund's
advisor to unaffiliated third parties who provide recordkeeping and
administrative services that would otherwise be performed by an affiliate of the
advisor.

The rate of the fee is determined by applying a formula that takes into account
all of the advisor's assets under management in the fund's investment strategy
(strategy assets). Strategy assets include the assets of the fund as well as
certain assets of other clients of the advisor outside the American Century fund
family (such as subadvised funds and separate accounts) that use very similar
investment teams and strategies. The use of strategy assets, rather than fund
assets, in calculating the fund's fee rate could allow the fund to realize
scheduled cost savings more quickly. However, it is possible that the fund's
strategy assets will not include assets of other client accounts or that any
such assets may not be sufficient to result in a lower fee rate.

MANAGEMENT FEES PAID
BY THE FUND TO THE
ADVISOR AS A PERCENTAGE
OF AVERAGE NET ASSETS
FOR THE FISCAL YEAR INVESTOR INSTITUTIONAL C R ADVISOR
ENDED OCTOBER 31, 2006 CLASS CLASS CLASS CLASS CLASS
--------------------------------------------------------------------------------
Ultra 0.99% 0.79% 0.99% 0.99% 0.74%
--------------------------------------------------------------------------------

A discussion regarding the basis for the Board of Directors' approval of the
fund's investment advisory contract with the advisor is available in the fund's
report to shareholders dated October 31, 2006.

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10

THE FUND MANAGEMENT TEAM

The advisor uses teams of portfolio managers and analysts to manage funds. The
teams meet regularly to review portfolio holdings and discuss purchase and sale
activity. Team members buy and sell securities for a fund as they see fit,
guided by the fund's investment objective and strategy.

The portfolio managers on the investment team who are jointly and primarily
responsible for the day-to-day management of the fund are identified below.

WADE W. SLOME

Mr. Slome, Vice President and Portfolio Manager, has been a member of the team
that manages the fund since joining American Century in June 1998. He was
promoted to portfolio manager in July 2002. He holds a bachelor's degree in
economics from the University of California - Los Angeles, and an MBA in finance
from Cornell University. He is a CFA charterholder.

TOM TELFORD

Mr. Telford, Vice President and Portfolio Manager, has been a member of the team
that manages the fund since June 2006. He joined American Century in July 1996
and became a portfolio manager in February 2000. He has a bachelor's degree in
business administration from Southern Methodist University and an MBA from
Wharton School of Business, University of Pennsylvania. He is a CFA
charterholder.

The statement of additional information provides additional information about
the other accounts managed by the portfolio managers, if any, the structure of
their compensation, and their ownership of fund securities.

FUNDAMENTAL INVESTMENT POLICIES

Fundamental investment policies contained in the statement of additional
information and the investment objectives of the fund may not be changed without
shareholder approval. The Board of Directors and/or the advisor may change any
other policies and investment strategies.

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11

INVESTING DIRECTLY WITH AMERICAN CENTURY

SERVICES AUTOMATICALLY AVAILABLE TO YOU

Most accounts automatically will have access to the services listed under WAYS
TO MANAGE YOUR ACCOUNT when the account is opened. If you do not want these
services, see CONDUCTING BUSINESS IN WRITING. If you have questions about the
services that apply to your account type, please call us.

CONDUCTING BUSINESS IN WRITING

If you prefer to conduct business in writing only, you can indicate this on the
account application. If you choose this option, you must provide written
instructions to invest, exchange and redeem. All account owners must sign
transaction instructions (with signatures guaranteed for redemptions in excess
of $100,000). By choosing this option, you are not eligible to enroll for
exclusive online account management to waive the account maintenance fee. See
ACCOUNT MAINTENANCE FEE in this section. If you want to add online and telephone
services later, you can complete an Investor Service Options form.

ACCOUNT MAINTENANCE FEE

If you hold Investor Class shares of any American Century fund, or Institutional
Class shares of the American Century Diversified Bond fund, in an American
Century account (i.e., not a financial intermediary or retirement plan account),
we may charge you a $12.50 semiannual account maintenance fee if the value of
those shares is less than $10,000. We will determine the amount of your total
eligible investments twice per year, generally the last Friday in October and
April. If the value of those investments is less than $10,000 at that time, we
will automatically redeem shares in one of your accounts to pay the $12.50 fee.
Please note that you may incur tax liability as a result of the redemption. In
determining your total eligible investment amount, we will include your
investments in all PERSONAL ACCOUNTS (including American Century Brokerage
accounts) registered under your Social Security number. We will not charge the
fee as long as you choose to manage your accounts exclusively online. You may
enroll for exclusive online account management on our Web site. To find out more
about exclusive online account management, visit americancentury.com/info/demo.

[graphic of triangle]

PERSONAL ACCOUNTS INCLUDE INDIVIDUAL ACCOUNTS, JOINT ACCOUNTS, UGMA/UTMA
ACCOUNTS, PERSONAL TRUSTS, COVERDELL EDUCATION SAVINGS ACCOUNTS, IRAS
(INCLUDING TRADITIONAL, ROTH, ROLLOVER, SEP-, SARSEP- AND SIMPLE-IRAS),
AND CERTAIN OTHER RETIREMENT ACCOUNTS. IF YOU HAVE ONLY BUSINESS,
BUSINESS RETIREMENT, EMPLOYER-SPONSORED OR AMERICAN CENTURY BROKERAGE
ACCOUNTS, YOU ARE CURRENTLY NOT SUBJECT TO THIS FEE, BUT YOU MAY BE
SUBJECT TO OTHER FEES.

WIRE PURCHASES

CURRENT INVESTORS: If you would like to make a wire purchase into an existing
account, your bank will need the following information. (To invest in a new
fund, please call us first to set up the new account.)

* American Century's bank information: Commerce Bank N.A., Routing No.
101000019, Account No. 2804918

* Your American Century account number and fund name

* Your name

* The contribution year (for IRAs only)

NEW INVESTORS: To make a wire purchase into a new account, please complete an
application prior to wiring money.

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12

WAYS TO MANAGE YOUR ACCOUNT

ONLINE
--------------------------------------------------------------------------------
americancentury.com

OPEN AN ACCOUNT: If you are a current or new investor, you can open an account
by completing and submitting our online application. Current investors also can
open an account by exchanging shares from another American Century account.

EXCHANGE SHARES: Exchange shares from another American Century account.

MAKE ADDITIONAL INVESTMENTS: Make an additional investment into an established
American Century account if you have authorized us to invest from your bank
account.

SELL SHARES*: Redeem shares and proceeds will be electronically transferred to
your authorized bank account.

* ONLINE REDEMPTIONS UP TO $25,000 PER DAY.

IN PERSON
--------------------------------------------------------------------------------
If you prefer to handle your transactions in person, visit one of our Investor
Centers and a representative can help you open an account, make additional
investments, and sell or exchange shares.

* 4500 Main Street, Kansas City, Missouri - 8 a.m. to 5 p.m., Monday - Friday

* 4917 Town Center Drive, Leawood, Kansas - 8 a.m. to 5 p.m., Monday - Friday,
8 a.m. to noon, Saturday

* 1665 Charleston Road, Mountain View, California - 8 a.m. to 5 p.m., Monday -
Friday

BY TELEPHONE
--------------------------------------------------------------------------------
INVESTOR SERVICES REPRESENTATIVE: 1-800-345-2021

INSTITUTIONAL SERVICE REPRESENTATIVE: 1-800-345-3533

BUSINESS, NOT-FOR-PROFIT AND EMPLOYER-SPONSORED RETIREMENT PLANS: 1-800-345-3533

AUTOMATED INFORMATION LINE: 1-800-345-8765

OPEN AN ACCOUNT: If you are a current investor, you can open an account by
exchanging shares from another American Century account.

EXCHANGE SHARES: Call or use our Automated Information Line if you have
authorized us to accept telephone instructions. The Automated Information Line
is available only to Investor Class shareholders.

MAKE ADDITIONAL INVESTMENTS: Call or use our Automated Information Line if you
have authorized us to invest from your bank account. The Automated Information
Line is available only to Investor Class shareholders.

SELL SHARES: Call a Service Representative.

BY MAIL OR FAX
--------------------------------------------------------------------------------
P.O. Box 419200, Kansas City, MO 64141-6200 - Fax: 816-340-7962

OPEN AN ACCOUNT: Send a signed, completed application and check or money order
payable to American Century Investments.

EXCHANGE SHARES: Send written instructions to exchange your shares from one
American Century account to another.

MAKE ADDITIONAL INVESTMENTS: Send your check or money order for at least $50
with an investment slip or $250 without an investment slip. If you don't have an
investment slip, include your name, address and account number on your check or
money order.

SELL SHARES: Send written instructions or a redemption form to sell shares. Call
a Service Representative to request a form.

AUTOMATICALLY
--------------------------------------------------------------------------------
OPEN AN ACCOUNT: Not available.

EXCHANGE SHARES: Send written instructions to set up an automatic exchange of
your shares from one American Century account to another.

MAKE ADDITIONAL INVESTMENTS: With the automatic investment service, you can
purchase shares on a regular basis. You must invest at least $50 per month per
account.

SELL SHARES: You may sell shares automatically by establishing Check-A-Month or
Automatic Redemption plans.

SEE ADDITIONAL POLICIES AFFECTING YOUR INVESTMENT FOR MORE INFORMATION ABOUT
INVESTING WITH US.

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13

INVESTING THROUGH A FINANCIAL INTERMEDIARY

The fund's C, R and Advisor Classes are intended for purchase by participants in
employer-sponsored retirement plans. Additionally, the fund's C and Advisor
Classes are intended for persons purchasing shares through FINANCIAL
INTERMEDIARIES that provide various administrative and distribution services.
For more information regarding employer-sponsored retirement plan types, please
see BUYING AND SELLING FUND SHARES in the statement of additional information.

[graphic of triangle]

FINANCIAL INTERMEDIARIES INCLUDE BANKS, BROKER-DEALERS,
INSURANCE COMPANIES, PLAN SPONSORS AND FINANCIAL PROFESSIONALS.

Although each class of shares represents an interest in the same fund, each has
a different cost structure, as described below. Which class is right for you
depends on many factors, including how long you plan to hold the shares, how
much you plan to invest, the fee structure of each class, and how you wish to
compensate your financial professional for the services provided to you. Your
financial professional can help you choose the option that is most appropriate.

The following chart provides a summary description of these classes.

C CLASS R CLASS AND ADVISOR CLASS
--------------------------------------------------------------------------------
No initial sales charge No initial sales charge
--------------------------------------------------------------------------------
Contingent deferred sales charge No contingent deferred
on redemptions within 12 months sales charge
--------------------------------------------------------------------------------
12b-1 fee of 1.00% 12b-1 fee of 0.50%(1)
--------------------------------------------------------------------------------
No conversion feature No conversion feature
--------------------------------------------------------------------------------
Aggregate purchases limited to Generally offered through
amounts less than $1,000,000; employer-sponsored
generally more appropriate for retirement plans and other
short-term investors fee-based arrangements(2)
--------------------------------------------------------------------------------

(1) WHILE THE R CLASS AND ADVISOR CLASS HAVE THE SAME 12B-1 FEE, THEIR
TOTAL ANNUAL FUND OPERATING EXPENSES WILL BE DIFFERENT BECAUSE OF THE
ADVISOR CLASS'S LOWER UNIFIED MANAGEMENT FEE. SEE PAGE 6 FOR MORE DETAILS.

(2) IRA ACCOUNTS IN R CLASS SHARES ESTABLISHED THROUGH FINANCIAL INTERMEDIARIES
PRIOR TO AUGUST 1, 2006, MAY MAKE ADDITIONAL PURCHASES.

CALCULATION OF CONTINGENT DEFERRED SALES CHARGE (CDSC)

C Class shares are sold at their net asset value without an initial sales
charge. For sales of C Class shares, the amount paid to your financial
professional is 1.00% of the amount invested. If you redeem your shares within
12 months of purchase, you will pay a CDSC of 1.00% of the original purchase
price or the current market value at redemption, whichever is less. The purpose
of the CDSC is to permit the fund's distributor to recoup all or a portion of
the up-front payment made to your financial professional.

The CDSC will not be charged on shares acquired through reinvestment of
dividends or distributions or increases in the net asset value of shares.

To minimize the amount of the CDSC you may pay when you redeem shares, the fund
will first redeem shares acquired through reinvested dividends and capital gain
distributions, which are not subject to a CDSC. Shares that have been in your
account long enough that they are not subject to a CDSC are redeemed next. For
any remaining redemption amount, shares will be sold in the order they were
purchased (earliest to latest).

The information regarding C Class sales charges provided herein is included free
of charge and in a clear and prominent format at americancentury.com in the
INVESTORS USING ADVISORS and INVESTMENT PROFESSIONALS portions of the Web site.
From the description of C Class shares, a hyperlink will take you directly to
this disclosure.

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14

CDSC WAIVERS

Any applicable CDSC may be waived in the following cases:

* redemptions through systematic withdrawal plans not exceeding annually:

* 12% of the lesser of the original purchase cost or current market
value for C Class shares

* distributions from IRAs due to attainment of age 59-1/2 for C Class shares

* required minimum distributions from retirement accounts upon reaching age
70-1/2

* tax-free returns of excess contributions to IRAs

* redemptions due to death or post-purchase disability

* exchanges, unless the shares acquired by exchange are redeemed within the
original CDSC period

* if no broker was compensated for the sale

EXCHANGES BETWEEN FUNDS (C CLASS)

You may exchange C Class shares of a fund for C Class shares of any other
American Century fund. You may not exchange from the C Class to any other class.
We will not charge a CDSC on the shares you exchange, regardless of the length
of time you have owned them. When you do redeem shares that have been exchanged,
the CDSC will be based on the date you purchased the original shares.

BUYING AND SELLING SHARES

Your ability to purchase, exchange, redeem and transfer shares will be affected
by the policies of the financial intermediary through which you do business.
Some policy differences may include

* minimum investment requirements

* exchange policies

* fund choices

* cutoff time for investments

* trading restrictions

In addition, your financial intermediary may charge a transaction fee for the
purchase or sale of fund shares. Those charges are retained by the financial
intermediary and are not shared with American Century or the fund. Please
contact your financial intermediary or plan sponsor for a complete description
of its policies. Copies of the fund's annual report, semiannual report and
statement of additional information are available from your financial
intermediary or plan sponsor.

The fund has authorized certain financial intermediaries to accept orders on the
fund's behalf. American Century has selling agreements with these financial
intermediaries requiring them to track the time investment orders are received
and to comply with procedures relating to the transmission of orders. Orders
must be received by the financial intermediary on the fund's behalf before the
time the net asset value is determined in order to receive that day's share
price. If those orders are transmitted to American Century and paid for in
accordance with the selling agreement, they will be priced at the net asset
value next determined after your request is received in the form required by the
financial intermediary.

SEE ADDITIONAL POLICIES AFFECTING YOUR INVESTMENT FOR MORE INFORMATION ABOUT
INVESTING WITH US.

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15

ADDITIONAL POLICIES AFFECTING YOUR INVESTMENT

MINIMUM INITIAL INVESTMENT AMOUNTS (OTHER THAN INSTITUTIONAL CLASS)

Unless otherwise specified below, the minimum initial investment amount to open
an account is $2,500. Financial intermediaries may open an account with $250,
but may require their clients to meet different investment minimums. See
INVESTING THROUGH A FINANCIAL INTERMEDIARY for more information.

--------------------------------------------------------------------------------
Broker-dealer sponsored wrap program accounts
and/or fee-based accounts No minimum
--------------------------------------------------------------------------------
Coverdell Education Savings Account (CESA) $2,000(1)
--------------------------------------------------------------------------------
Employer-sponsored retirement plans No minimum
--------------------------------------------------------------------------------

(1) THE MINIMUM INITIAL INVESTMENT FOR FINANCIAL INTERMEDIARIES IS $250.
FINANCIAL INTERMEDIARIES MAY HAVE DIFFERENT MINIMUMS FOR THEIR CLIENTS.

SUBSEQUENT PURCHASES

There is a $50 minimum for subsequent purchases. See WAYS TO MANAGE YOUR ACCOUNT
for more information about making additional investments directly with American
Century. However, there is no subsequent purchase minimum for financial
intermediaries or employer-sponsored retirement plans, but financial
intermediaries may require their clients to meet different subsequent purchase
requirements.

ELIGIBILITY FOR INSTITUTIONAL CLASS SHARES

The Institutional Class shares are made available for purchase by large
institutional shareholders such as bank trust departments, corporations,
retirement plans, endowments, foundations and financial advisors that meet the
fund's minimum investment requirements. Institutional Class shares are not
available for purchase by insurance companies for variable annuity and variable
life products.

MINIMUM INITIAL INVESTMENT AMOUNTS (INSTITUTIONAL CLASS)

The minimum initial investment amount is $5 million ($3 million for endowments
and foundations) per fund. If you invest with us through a financial
intermediary, this requirement may be met if your financial intermediary
aggregates your investments with those of other clients into a single group, or
omnibus, account that meets the minimum. The minimum investment requirement may
be waived if you, or your financial intermediary if you invest through an
omnibus account, have an aggregate investment in our family of funds of $10
million or more ($5 million for endowments and foundations). In addition,
financial intermediaries or plan recordkeepers may require retirement plans to
meet certain other conditions, such as plan size or a minimum level of assets
per participant, in order to be eligible to purchase Institutional Class shares.

REDEMPTIONS

If you sell your C Class shares within 12 months of their purchase, you will pay
a sales charge. Your redemption proceeds will be calculated using the NET ASSET
VALUE (NAV) next determined after we receive your transaction request in good
order.

[graphic of triangle]

A FUND'S NET ASSET VALUE, OR NAV, IS THE PRICE OF THE FUND'S SHARES.

------
16

shares, unless you provide us with satisfactory proof that your purchase funds
have cleared. Investments by wire generally require only a one-day holding
period. If you change your address, we may require that any redemption request
made within 15 days be submitted in writing and be signed by all authorized
signers with their signatures guaranteed. If you change your bank information,
we may impose a 15-day holding period before we will transfer or wire redemption
proceeds to your bank. Please remember, if you request redemptions by wire, $10
will be deducted from the amount redeemed. Your bank also may charge a fee.

In addition, we reserve the right to honor certain redemptions with securities,
rather than cash, as described in the next section.

SPECIAL REQUIREMENTS FOR LARGE REDEMPTIONS

If, during any 90-day period, you redeem fund shares worth more than $250,000
(or 1% of the value of a fund's assets if that amount is less than $250,000), we
reserve the right to pay part or all of the redemption proceeds in excess of
this amount in readily marketable securities instead of in cash. The portfolio
managers would select these securities from the fund's portfolio.

We will value these securities in the same manner as we do in computing the
fund's net asset value. We may provide these securities in lieu of cash without
prior notice. Also, if payment is made in securities, you may have to pay
brokerage or other transaction costs to convert the securities to cash.

If your redemption would exceed this limit and you would like to avoid being
paid in securities, please provide us with an unconditional instruction to
redeem at least 15 days prior to the date on which the redemption transaction is
to occur. The instruction must specify the dollar amount or number of shares to
be redeemed and the date of the transaction. This minimizes the effect of the
redemption on a fund and its remaining investors.

REDEMPTION OF SHARES IN ACCOUNTS BELOW MINIMUM

If your account balance falls below the minimum initial investment amount for
any reason other than as a result of market fluctuation, American Century
reserves the right to redeem the shares in the account and send the proceeds to
your address of record. Prior to doing so, we will notify you and give you 90
days to meet the minimum. C Class shares redeemed in this manner may be subject
to a sales charge if held less than the applicable period. Please note that you
may incur tax liability as a result of the redemption. For Institutional Class
shares, we reserve the right to convert your shares to Investor Class shares of
the same fund. The Investor Class shares have a unified management fee that is
0.20% higher than the Institutional Class.

SIGNATURE GUARANTEES

A signature guarantee - which is different from a notarized signature - is a
warranty that the signature presented is genuine. We may require a signature
guarantee for the following transactions.

* You have chosen to conduct business in writing only and would like to
redeem over $100,000.

* Your redemption or distribution check, Check-A-Month or automatic
redemption is made payable to someone other than the account owners.

* Your redemption proceeds or distribution amount is sent by EFT (ACH or
wire) to a destination other than your personal bank account.

* You are transferring ownership of an account over $100,000.

* You change your address and request a redemption over $100,000 within 15
days.

* You change your bank information and request a redemption within 15 days.

We reserve the right to require a signature guarantee for other transactions, at
our discretion.

------
17

MODIFYING OR CANCELING AN INVESTMENT

Investment instructions are irrevocable. That means that once you have mailed or
otherwise transmitted your investment instruction, you may not modify or cancel
it. Each fund reserves the right to suspend the offering of shares for a period
of time and to reject any specific investment (including a purchase by
exchange). Additionally, we may refuse a purchase if, in our judgment, it is of
a size that would disrupt the management of a fund.

ABUSIVE TRADING PRACTICES

Short-term trading and other so-called market timing practices are not defined
or explicitly prohibited by any federal or state law. However, short-term
trading and other abusive trading practices may disrupt portfolio management
strategies and harm fund performance. If the cumulative amount of short-term
trading activity is significant relative to a fund's net assets, the fund may
incur trading costs that are higher than necessary as securities are first
purchased then quickly sold to meet the redemption request. In such case, the
fund's performance could be negatively impacted by the increased trading costs
created by short-term trading if the additional trading costs are significant.

Because of the potentially harmful effects of abusive trading practices, the
fund's Board of Directors has approved American Century's abusive trading
policies and procedures, which are designed to reduce the frequency and effect
of these activities in our funds. These policies and procedures include
monitoring trading activity, imposing trading restrictions on certain accounts,
imposing redemption fees on certain funds, and using fair value pricing when
current market prices are not readily available. Although these efforts are
designed to discourage abusive trading practices, they cannot eliminate the
possibility that such activity will occur. American Century seeks to exercise
its judgment in implementing these tools to the best of its ability in a manner
that it believes is consistent with shareholder interests.

American Century uses a variety of techniques to monitor for and detect abusive
trading practices. These techniques may vary depending on the type of fund, the
class of shares or whether the shares are held directly or indirectly with
American Century. They may change from time to time as determined by American
Century in its sole discretion. To minimize harm to the funds and their
shareholders, we reserve the right to reject any purchase order (including
exchanges) from any shareholder we believe has a history of abusive trading or
whose trading, in our judgment, has been or may be disruptive to the funds. In
making this judgment, we may consider trading done in multiple accounts under
common ownership or control.

Currently, for shares held directly with American Century, we may deem the sale
of all or a substantial portion of a shareholder's purchase of fund shares to be
abusive if the sale is made

* within seven days of the purchase, or

* within 30 days of the purchase, if it happens more than once per year.

To the extent practicable, we try to use the same approach for defining abusive
trading for shares held through financial intermediaries. American Century
reserves the right, in its sole discretion, to identify other trading practices
as abusive and to modify its monitoring and other practices as necessary to deal
with novel or unique abusive trading practices.

In addition, American Century reserves the right to accept purchases and
exchanges in excess of the trading restrictions discussed above if it believes
that such transactions would not be inconsistent with the best interests of fund
shareholders or this policy.

------
18

Century handles, there can be no assurance that American Century's efforts will
identify all trades or trading practices that may be considered abusive. In
addition, American Century's ability to monitor trades that are placed by
individual shareholders within group, or omnibus, accounts maintained by
financial intermediaries is severely limited because American Century generally
does not have access to the underlying shareholder account information. However,
American Century monitors aggregate trades placed in omnibus accounts and seeks
to work with financial intermediaries to discourage shareholders from engaging
in abusive trading practices and to impose restrictions on excessive trades.
There may be limitations on the ability of financial intermediaries to impose
restrictions on the trading practices of their clients. As a result, American
Century's ability to monitor and discourage abusive trading practices in omnibus
accounts may be limited.

YOUR RESPONSIBILITY FOR UNAUTHORIZED TRANSACTIONS

American Century and its affiliated companies use procedures reasonably designed
to confirm that telephone, electronic and other instructions are genuine. These
procedures include recording telephone calls, requesting personalized security
codes or other information, and sending confirmation of transactions. If we
follow these procedures, we are not responsible for any losses that may occur
due to unauthorized instructions. For transactions conducted over the Internet,
we recommend the use of a secure Internet browser. In addition, you should
verify the accuracy of your confirmation statements immediately after you
receive them.

A NOTE ABOUT MAILINGS TO SHAREHOLDERS

To reduce the amount of mail you receive from us, we may deliver a single copy
of certain investor documents (such as shareholder reports and prospectuses) to
investors who share an address, even if accounts are registered under different
names. If you prefer to receive multiple copies of these documents individually
addressed, please call us or your financial professional. For American Century
Brokerage accounts, please call 1-888-345-2071.

RIGHT TO CHANGE POLICIES

We reserve the right to change any stated investment requirement, including
those that relate to purchases, exchanges and redemptions. We also may alter,
add or discontinue any service or privilege. Changes may affect all investors or
only those in certain classes or groups. In addition, from time to time we may
waive a policy on a case-by-case basis, as the advisor deems appropriate.

------
19

SHARE PRICE AND DISTRIBUTIONS

SHARE PRICE

American Century will price the fund shares you purchase, exchange or redeem at
the net asset value (NAV) next determined after your order is received and
accepted by the fund's transfer agent, or other financial intermediary with the
authority to accept orders on the fund's behalf. We determine the NAV of each
fund as of the close of regular trading (usually 4 p.m. Eastern time) on the New
York Stock Exchange (NYSE) on each day the NYSE is open. On days when the NYSE
is closed (including certain U.S. national holidays), we do not calculate the
NAV. A fund's NAV is the current value of the fund's assets, minus any
liabilities, divided by the number of shares outstanding.

The fund values portfolio securities for which market quotations are readily
available at their market price. As a general rule, equity securities listed on
a U.S. exchange are valued at the last current reported sale price as of the
time of valuation. Securities listed on the NASDAQ National Market System
(Nasdaq) are valued at the Nasdaq Official Closing Price (NOCP), as determined
by Nasdaq, or lacking an NOCP, at the last current reported sale price as of the
time of valuation. The fund may use pricing services to assist in the
determination of market value. Unlisted securities for which market quotations
are readily available are valued at the last quoted sale price or the last
quoted ask price, as applicable, except that debt obligations with 60 days or
less remaining until maturity may be valued at amortized cost. Exchange-traded
options, futures and options on futures are valued at the settlement price as
determined by the appropriate clearing corporation.

If the fund determines that the market price for a portfolio security is not
readily available or that the valuation methods mentioned above do not reflect
the security's fair value, such security is valued at its fair value as
determined in good faith by, or in accordance with procedures adopted by, the
fund's board or its designee (a process referred to as "fair valuing" the
security). Circumstances that may cause the fund to fair value a security
include, but are not limited to:

* if, after the close of the foreign exchange on which a portfolio security
is principally traded, but before the close of the NYSE, an event occurs that
may materially affect the value of the security;

* a debt security has been declared in default; or

* trading in a security has been halted during the trading day.

If such circumstances occur, the fund will fair value the security if the fair
valuation would materially impact the fund's NAV. While fair value
determinations involve judgments that are inherently subjective, these
determinations are made in good faith in accordance with procedures adopted by
the fund's board.

The effect of using fair value determinations is that the fund's NAV will be
based, to some degree, on security valuations that the board or its designee
believes are fair rather than being solely determined by the market.

With respect to any portion of the fund's assets that are invested in one or
more open-end management investment companies that are registered with the SEC
(known as registered investment companies, or RICs), the fund's NAV will be
calculated based upon the NAVs of such RICs. These RICs are required by law to
explain the circumstances under which they will use fair value pricing and the
effects of using fair value pricing in their prospectuses.

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20

Securities and other assets quoted in foreign currencies are valued in U.S.
dollars based on the prevailing exchange rates on that day.

Trading of securities in foreign markets may not take place every day the NYSE
is open. Also, trading in some foreign markets and on some electronic trading
networks may take place on weekends or holidays when the fund's NAV is not
calculated. So, the value of the fund's portfolio may be affected on days when
you will not be able to purchase, exchange or redeem fund shares.

DISTRIBUTIONS

Federal tax laws require each fund to make distributions to its shareholders in
order to qualify as a "regulated investment company." Qualification as a
regulated investment company means the fund should not be subject to state or
federal income tax on amounts distributed. The distributions generally consist
of dividends and interest received by a fund, as well as CAPITAL GAINS realized
by a fund on the sale of its investment securities. The fund generally pays
distributions from net income and capital gains, if any, once a year in
December. The fund may make more frequent distributions, if necessary, to comply
with Internal Revenue Code provisions.

[graphic of triangle]

CAPITAL GAINS ARE INCREASES IN THE VALUES OF CAPITAL ASSETS,
SUCH AS STOCK, FROM THE TIME THE ASSETS ARE PURCHASED.

You will participate in fund distributions when they are declared, starting the
next business day after your purchase is effective. For example, if you purchase
shares on a day that a distribution is declared, you will not receive that
distribution. If you redeem shares, you will receive any distribution declared
on the day you redeem. If you redeem all shares, we will include any
distributions received with your redemption proceeds.

Participants in tax-deferred retirement plans must reinvest all distributions.
For investors investing through taxable accounts, we will reinvest distributions
unless you elect to have dividends and/or capital gains sent to another American
Century account, to your bank electronically, to your home address or to another
person or address by check.

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21

TAXES

The tax consequences of owning shares of the fund will vary depending on whether
you own them through a taxable or tax-deferred account. Tax consequences result
from distributions by the fund of dividend and interest income they have
received or capital gains they have generated through their investment
activities. Tax consequences also may result when investors sell fund shares
after the net asset value has increased or decreased.

Tax-Deferred Accounts

If you purchase fund shares through a tax-deferred account, such as an IRA or a
qualified employer-sponsored retirement plan, income and capital gains
distributions usually will not be subject to current taxation but will
accumulate in your account under the plan on a tax-deferred basis. Likewise,
moving from one fund to another fund within a plan or tax-deferred account
generally will not cause you to be taxed. For information about the tax
consequences of making purchases or withdrawals through a tax-deferred account,
please consult your plan administrator, your summary plan description or a tax
advisor.

Taxable Accounts

If you own fund shares through a taxable account, you may be taxed on your
investments if the fund makes distributions or if you sell your fund shares.

Taxability of Distributions

Fund distributions may consist of income, such as dividends and interest earned
by a fund from its investments, or capital gains generated by a fund from the
sale of investment securities. Distributions of income are taxed as ordinary
income, unless they are designated as QUALIFIED DIVIDEND INCOME and you meet a
minimum required holding period with respect to your shares of the fund, in
which case distributions of income are taxed as long-term capital gains.

[graphic of triangle]

QUALIFIED DIVIDEND INCOME IS A DIVIDEND RECEIVED BY THE FUND FROM THE
STOCK OF A DOMESTIC OR QUALIFYING FOREIGN CORPORATION, PROVIDED THAT THE
FUND HAS HELD THE STOCK FOR A REQUIRED HOLDING PERIOD.

For capital gains and for income distributions designated as qualified dividend
income, the following rates apply:

TAX RATE FOR 10% TAX RATE FOR
TYPE OF DISTRIBUTION AND 15% BRACKETS ALL OTHER BRACKETS
--------------------------------------------------------------------------------
Short-term capital gains Ordinary Income Ordinary Income
--------------------------------------------------------------------------------
Long-term capital gains (> 1 year)
and Qualified Dividend Income 5% 15%
--------------------------------------------------------------------------------

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22

If the fund's distributions exceed its taxable income and capital gains realized
during the tax year, all or a portion of the distributions made by the fund in
that tax year will be considered a return of capital. A return of capital
distribution is generally not subject to tax, but will reduce your cost basis in
the fund and result in higher realized capital gains (or lower realized capital
losses) upon the sale of fund shares.

The tax status of any distributions of capital gains is determined by how long
the fund held the underlying security that was sold, not by how long you have
been invested in the fund, or whether you reinvest your distributions in
additional shares or take them in cash. For taxable accounts, American Century
or your financial intermediary will inform you of the tax status of fund
distributions for each calendar year in an annual tax mailing.

Distributions also may be subject to state and local taxes. Because everyone's
tax situation is unique, you may want to consult your tax professional about
federal, state and local tax consequences.

Taxes on Transactions

Your redemptions-including exchanges to other American Century funds-are subject
to capital gains tax. The table above can provide a general guide for your
potential tax liability when selling or exchanging fund shares. Short-term
capital gains are gains on fund shares you held for 12 months or less. Long-term
capital gains are gains on fund shares you held for more than 12 months. If your
shares decrease in value, their sale or exchange will result in a long-term or
short-term capital loss. However, you should note that loss realized upon the
sale or exchange of shares held for six months or less will be treated as a
long-term capital loss to the extent of any distribution of long-term capital
gain to you with respect to those shares. If a loss is realized on the
redemption of fund shares, the reinvestment in additional fund shares within 30
days before or after the redemption may be subject to the wash sale rules of the
Internal Revenue Code. This may result in a postponement of the recognition of
such loss for federal income tax purposes.

If you have not certified to us that your Social Security number or tax
identification number is correct and that you are not subject to withholding, we
are required to withhold and pay to the IRS the applicable federal withholding
tax rate on taxable dividends, capital gains distributions and redemption
proceeds.

Buying a Dividend

Purchasing fund shares in a taxable account shortly before a distribution is
sometimes known as buying a dividend. In taxable accounts, you must pay income
taxes on the distribution whether you reinvest the distribution or take it in
cash. In addition, you will have to pay taxes on the distribution whether the
value of your investment decreased, increased or remained the same after you
bought the fund shares.

The risk in buying a dividend is that a fund's portfolio may build up taxable
gains throughout the period covered by a distribution, as securities are sold at
a profit. The fund distributes those gains to you, after subtracting any losses,
even if you did not own the shares when the gains occurred.

If you buy a dividend, you incur the full tax liability of the distribution
period, but you may not enjoy the full benefit of the gains realized in the
fund's portfolio.

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23

MULTIPLE CLASS INFORMATION

American Century offers five classes of shares of the fund: Investor Class,
Institutional Class, C Class, R Class and Advisor Class.

The classes have different fees, expenses and/or minimum investment
requirements. The difference in the fee structures between the classes is the
result of their separate arrangements for shareholder and distribution services.
It is not the result of any difference in advisory or custodial fees or other
expenses related to the management of the fund's assets, which do not vary by
class. Different fees and expenses will affect performance.

Except as described below, all classes of shares of the fund have identical
voting, dividend, liquidation and other rights, preferences, terms and
conditions. The only differences between the classes are (a) each class may be
subject to different expenses specific to that class; (b) each class has a
different identifying designation or name; (c) each class has exclusive voting
rights with respect to matters solely affecting such class; (d) each class may
have different exchange privileges; and (e) the Institutional Class may provide
for automatic conversion from that class into shares of the Investor Class of
the same fund.

Service, Distribution and Administrative Fees

Investment Company Act Rule 12b-1 permits mutual funds that adopt a written plan
to pay certain expenses associated with the distribution of their shares out of
fund assets. The fund's Advisor Class, C Class and R Class shares have a 12b-1
plan. The plans provide for the fund to pay annual fees of 1.00% for C Class and
0.50% for Advisor and R Classes to the distributor for certain ongoing
shareholder and administrative services and for distribution services, including
past distribution services. Under the Advisor Class Plan, the fund's Advisor
Class pays the distributor an annual fee of 0.50% of Advisor Class average net
assets, half for certain shareholder and administrative services and half for
distribution services, including past distribution services. The distributor
pays all or a portion of such fees to the financial intermediaries that make the
classes available. Because these fees are used to pay for services that are not
related to prospective sales of the fund, each class will continue to make
payments under its plan even if it is closed to new investors. Because these
fees are paid out of the fund's assets on an ongoing basis, over time these fees
will increase the cost of your investment and may cost you more than paying
other types of sales charges. For additional information about the plans and
their terms, see MULTIPLE CLASS STRUCTURE in the statement of additional
information.

Certain financial intermediaries perform recordkeeping and administrative
services for their clients that would otherwise be performed by American
Century's transfer agent. In some circumstances, the advisor will pay such
service providers a fee for performing those services. Also, the advisor and the
fund's distributor may make payments for various additional services or other
expenses out of their profits or other available sources. Such payments may be
made for one or more of the following: (1) distribution services, which include
expenses incurred by intermediaries for their sales activities with respect to
the fund, such as preparing, printing and distributing sales literature and
advertising materials and compensating registered representatives or other
employees of such financial intermediary for their sales activities; (2)
shareholder services, such as providing individual and custom investment
advisory services to clients of the financial intermediary; and (3) marketing
and promotional services, including business planning assistance, educating
personnel about the fund, and sponsorship of sales meetings, which may include
covering costs of providing speakers, meals and other entertainment. The
distributor may sponsor seminars and conferences designed to educate
intermediaries about the fund and may cover the expenses associated with
attendance at such meetings, including travel costs. These payments and
activities are intended to provide an incentive to intermediaries to sell the
fund by ensuring that they are educated about the fund, and to help such
intermediaries defray costs associated with offering the fund. The amount of any
payments described by this paragraph is determined by the advisor or the
distributor, and all such amounts are paid out of the available assets of the
advisor and distributor, and not by you or the fund. As a result, the total
expense ratio of the fund will not be affected by any such payments.

------
24

FINANCIAL HIGHLIGHTS

UNDERSTANDING THE FINANCIAL HIGHLIGHTS

The tables on the next few pages itemize what contributed to the changes in
share price during the most recently ended fiscal year. They also show the
changes in share price for this period in comparison to changes over the last
five fiscal years (or a shorter period if the share class is not five years
old).

On a per-share basis, each table includes as appropriate

* share price at the beginning of the period

* investment income and capital gains or losses

* distributions of income and capital gains paid to investors

* share price at the end of the period

Each table also includes some key statistics for the period as appropriate

* TOTAL RETURN - the overall percentage of return of the fund, assuming the
reinvestment of all distributions

* EXPENSE RATIO - the operating expenses of the fund as a percentage of
average net assets

* NET INCOME RATIO - the net investment income of the fund as a percentage
of average net assets

* PORTFOLIO TURNOVER - the percentage of the fund's investment portfolio
that is replaced during the period

The Financial Highlights that follow have been audited by Deloitte & Touche LLP.
The fund's Report of Independent Registered Public Accounting Firm and the
financial statements are included in the fund's annual report, which is
available upon request.

------
25

ULTRA FUND

Investor Class

FOR A SHARE OUTSTANDING THROUGHOUT THE YEARS ENDED OCTOBER 31
------------------------------------------------------------------------------------------
2006 2005 2004 2003 2002
------------------------------------------------------------------------------------------
PER-SHARE DATA
------------------------------------------------------------------------------------------
Net Asset Value, Beginning of Period $29.02 $27.17 $26.01 $21.83 $25.09
------------------------------------------------------------------------------------------
Income From Investment Operations
--------------------------------------
Net Investment Income (Loss)(1) (0.06) 0.02 (0.05) (0.02) 0.06
--------------------------------------
Net Realized and
Unrealized Gain (Loss) (0.37) 1.83 1.21 4.26 (3.32)
------------------------------------------------------------------------------------------
Total From Investment Operations (0.43) 1.85 1.16 4.24 (3.26)
------------------------------------------------------------------------------------------
Distributions
--------------------------------------
From Net Investment Income (0.04) - - (0.06) -
------------------------------------------------------------------------------------------
Net Asset Value, End of Period $28.55 $29.02 $27.17 $26.01 $21.83
==========================================================================================
TOTAL RETURN(2) (1.51)% 6.81% 4.46% 19.50% (12.99)%

RATIOS/SUPPLEMENTAL DATA
------------------------------------------------------------------------------------------
Ratio of Operating Expenses
to Average Net Assets 0.99% 0.99% 0.99% 1.00% 0.99%
--------------------------------------
Ratio of Net Investment Income (Loss)
to Average Net Assets (0.15)% 0.09% (0.20)% (0.09)% 0.24%
--------------------------------------
Portfolio Turnover Rate 62% 33% 34% 82% 92%
--------------------------------------
Net Assets, End of Period
(in millions) $13,482 $18,904 $20,708 $21,341 $18,616
------------------------------------------------------------------------------------------

(1) COMPUTED USING AVERAGE SHARES OUTSTANDING THROUGHOUT THE PERIOD.

(2) TOTAL RETURN ASSUMES REINVESTMENT OF NET INVESTMENT INCOME AND CAPITAL
GAINS DISTRIBUTIONS, IF ANY. THE TOTAL RETURN OF THE CLASSES MAY NOT
PRECISELY REFLECT THE CLASS EXPENSE DIFFERENCES BECAUSE OF THE IMPACT OF
CALCULATING THE NET ASSET VALUE TO TWO DECIMAL PLACES. IF NET ASSET VALUES
WERE CALCULATED TO THREE DECIMAL PLACES, THE TOTAL RETURN DIFFERENCES WOULD
MORE CLOSELY REFLECT THE CLASS EXPENSE DIFFERENCES. THE CALCULATION OF NET
ASSET VALUES TO TWO DECIMAL PLACES IS MADE IN ACCORDANCE WITH SEC
GUIDELINES AND DOES NOT RESULT IN ANY GAIN OR LOSS OF VALUE BETWEEN ONE
CLASS AND ANOTHER.

------
26

ULTRA FUND

Institutional Class

FOR A SHARE OUTSTANDING THROUGHOUT THE YEARS ENDED OCTOBER 31
----------------------------------------------------------------------------------------------------
2006 2005 2004 2003 2002
----------------------------------------------------------------------------------------------------
PER-SHARE DATA
----------------------------------------------------------------------------------------------------
Net Asset Value, Beginning of Period $29.38 $27.44 $26.22 $22.02 $25.24
----------------------------------------------------------------------------------------------------
Income From Investment Operations
---------------------------------------
Net Investment Income (Loss)(1) -(2) 0.07 -(2) 0.02 0.11
---------------------------------------
Net Realized and
Unrealized Gain (Loss) (0.38) 1.87 1.22 4.29 (3.33)
----------------------------------------------------------------------------------------------------
Total From Investment Operations (0.38) 1.94 1.22 4.31 (3.22)
----------------------------------------------------------------------------------------------------
Distributions
---------------------------------------
From Net Investment Income (0.10) - - (0.11) -
----------------------------------------------------------------------------------------------------
Net Asset Value, End of Period $28.90 $29.38 $27.44 $26.22 $22.02
====================================================================================================
TOTAL RETURN(3) (1.33)% 7.07% 4.65% 19.66% (12.76)%

RATIOS/SUPPLEMENTAL DATA
----------------------------------------------------------------------------------------------------
Ratio of Operating Expenses
to Average Net Assets 0.79% 0.79% 0.79% 0.80% 0.79%
---------------------------------------
Ratio of Net Investment Income (Loss)
to Average Net Assets 0.05% 0.29% 0.00% 0.11% 0.44%
---------------------------------------
Portfolio Turnover Rate 62% 33% 34% 82% 92%
---------------------------------------
Net Assets, End of Period
(in thousands) $1,073,767 $1,460,343 $1,055,145 $822,333 $556,316
----------------------------------------------------------------------------------------------------

(1) COMPUTED USING AVERAGE SHARES OUTSTANDING THROUGHOUT THE PERIOD.

(2) PER-SHARE AMOUNT WAS LESS THAN $0.005.

(3) TOTAL RETURN ASSUMES REINVESTMENT OF NET INVESTMENT INCOME AND CAPITAL
GAINS DISTRIBUTIONS, IF ANY. THE TOTAL RETURN OF THE CLASSES MAY NOT
PRECISELY REFLECT THE CLASS EXPENSE DIFFERENCES BECAUSE OF THE IMPACT OF
CALCULATING THE NET ASSET VALUE TO TWO DECIMAL PLACES. IF NET ASSET VALUES
WERE CALCULATED TO THREE DECIMAL PLACES, THE TOTAL RETURN DIFFERENCES WOULD
MORE CLOSELY REFLECT THE CLASS EXPENSE DIFFERENCES. THE CALCULATION OF NET
ASSET VALUES TO TWO DECIMAL PLACES IS MADE IN ACCORDANCE WITH SEC
GUIDELINES AND DOES NOT RESULT IN ANY GAIN OR LOSS OF VALUE BETWEEN ONE
CLASS AND ANOTHER.

------
27

ULTRA FUND

C Class

FOR A SHARE OUTSTANDING THROUGHOUT THE YEARS ENDED OCTOBER 31
-------------------------------------------------------------------------------------------
2006 2005 2004 2003 2002
-------------------------------------------------------------------------------------------
PER-SHARE DATA
-------------------------------------------------------------------------------------------
Net Asset Value, Beginning of Period $27.96 $26.44 $25.57 $21.59 $25.09
-------------------------------------------------------------------------------------------
Income From Investment Operations
---------------------------------------
Net Investment Income (Loss)(1) (0.34) (0.26) (0.32) (0.26) (0.19)
---------------------------------------
Net Realized and
Unrealized Gain (Loss) (0.36) 1.78 1.19 4.24 (3.31)
-------------------------------------------------------------------------------------------
Total From Investment Operations (0.70) 1.52 0.87 3.98 (3.50)
-------------------------------------------------------------------------------------------
Net Asset Value, End of Period $27.26 $27.96 $26.44 $25.57 $21.59
===========================================================================================
TOTAL RETURN(2) (2.50)% 5.75% 3.40% 18.43% (13.95)%

RATIOS/SUPPLEMENTAL DATA
-------------------------------------------------------------------------------------------
Ratio of Operating Expenses
to Average Net Assets 1.99% 1.99% 1.99% 2.00% 1.99%
---------------------------------------
Ratio of Net Investment Income (Loss)
to Average Net Assets (1.15)% (0.91)% (1.20)% (1.09)% (0.76)%
---------------------------------------
Portfolio Turnover Rate 62% 33% 34% 82% 92%
---------------------------------------
Net Assets, End of Period
(in thousands) $3,342 $5,601 $4,836 $2,232 $502
-------------------------------------------------------------------------------------------

(1) COMPUTED USING AVERAGE SHARES OUTSTANDING THROUGHOUT THE PERIOD.

(2) TOTAL RETURN ASSUMES REINVESTMENT OF NET INVESTMENT INCOME AND CAPITAL
GAINS DISTRIBUTIONS, IF ANY, AND DOES NOT REFLECT APPLICABLE SALES CHARGES.
THE TOTAL RETURN OF THE CLASSES MAY NOT PRECISELY REFLECT THE CLASS EXPENSE
DIFFERENCES BECAUSE OF THE IMPACT OF CALCULATING THE NET ASSET VALUE TO TWO
DECIMAL PLACES. IF NET ASSET VALUES WERE CALCULATED TO THREE DECIMAL
PLACES, THE TOTAL RETURN DIFFERENCES WOULD MORE CLOSELY REFLECT THE CLASS
EXPENSE DIFFERENCES. THE CALCULATION OF NET ASSET VALUES TO TWO DECIMAL
PLACES IS MADE IN ACCORDANCE WITH SEC GUIDELINES AND DOES NOT RESULT IN ANY
GAIN OR LOSS OF VALUE BETWEEN ONE CLASS AND ANOTHER.

------
28

ULTRA FUND

R Class

FOR A SHARE OUTSTANDING THROUGHOUT THE YEARS ENDED OCTOBER 31 (EXCEPT AS NOTED)
---------------------------------------------------------------------------------------
2006 2005 2004 2003(1)
---------------------------------------------------------------------------------------
PER-SHARE DATA
---------------------------------------------------------------------------------------
Net Asset Value, Beginning of Period $28.72 $27.01 $25.99 $24.87
---------------------------------------------------------------------------------------
Income From Investment Operations
---------------------------------------
Net Investment Income (Loss)(2) (0.21) (0.12) (0.22) (0.04)
---------------------------------------
Net Realized and
Unrealized Gain (Loss) (0.36) 1.83 1.24 1.16
---------------------------------------------------------------------------------------
Total From Investment Operations (0.57) 1.71 1.02 1.12
---------------------------------------------------------------------------------------
Net Asset Value, End of Period $28.15 $28.72 $27.01 $25.99
=======================================================================================
TOTAL RETURN(3) (1.98)% 6.33% 3.92% 4.50%

RATIOS/SUPPLEMENTAL DATA
---------------------------------------------------------------------------------------
Ratio of Operating Expenses
to Average Net Assets 1.49% 1.44%(4) 1.49% 1.50%(5)
---------------------------------------
Ratio of Net Investment Income (Loss)
to Average Net Assets (0.65)% (0.36)%(4) (0.70)% (0.81)%(5)
---------------------------------------
Portfolio Turnover Rate 62% 33% 34% 82%(6)
---------------------------------------
Net Assets, End of Period
(in thousands) $8,922 $8,367 $4,545 $3
---------------------------------------------------------------------------------------

(1) AUGUST 29, 2003 (COMMENCEMENT OF SALE) THROUGH OCTOBER 31, 2003.

(2) COMPUTED USING AVERAGE SHARES OUTSTANDING THROUGHOUT THE PERIOD.

(3) TOTAL RETURN ASSUMES REINVESTMENT OF NET INVESTMENT INCOME AND CAPITAL
GAINS DISTRIBUTIONS, IF ANY. TOTAL RETURNS FOR PERIODS LESS THAN ONE YEAR
ARE NOT ANNUALIZED. THE TOTAL RETURN OF THE CLASSES MAY NOT PRECISELY
REFLECT THE CLASS EXPENSE DIFFERENCES BECAUSE OF THE IMPACT OF CALCULATING
THE NET ASSET VALUE TO TWO DECIMAL PLACES. IF NET ASSET VALUES WERE
CALCULATED TO THREE DECIMAL PLACES, THE TOTAL RETURN DIFFERENCES WOULD MORE
CLOSELY REFLECT THE CLASS EXPENSE DIFFERENCES. THE CALCULATION OF NET ASSET
VALUES TO TWO DECIMAL PLACES IS MADE IN ACCORDANCE WITH SEC GUIDELINES AND
DOES NOT RESULT IN ANY GAIN OR LOSS OF VALUE BETWEEN ONE CLASS AND ANOTHER.

(4) DURING THE YEAR ENDED OCTOBER 31, 2005, THE CLASS RECEIVED A PARTIAL
REIMBURSEMENT OF ITS DISTRIBUTION AND SERVICE FEE. HAD FEES NOT BEEN
REIMBURSED THE ANNUALIZED RATIO OF OPERATING EXPENSES TO AVERAGE NET ASSETS
AND ANNUALIZED RATIO OF NET INVESTMENT INCOME (LOSS) TO AVERAGE NET ASSETS
WOULD HAVE BEEN 1.49% AND (0.41)%, RESPECTIVELY.

(5) ANNUALIZED.

(6) PORTFOLIO TURNOVER IS CALCULATED AT THE FUND LEVEL. PERCENTAGE INDICATED
WAS CALCULATED FOR THE YEAR ENDED OCTOBER 31, 2003.

------
29

ULTRA FUND

Advisor Class

FOR A SHARE OUTSTANDING THROUGHOUT THE YEARS ENDED OCTOBER 31
----------------------------------------------------------------------------------------------
2006 2005 2004 2003 2002
----------------------------------------------------------------------------------------------
PER-SHARE DATA
----------------------------------------------------------------------------------------------
Net Asset Value, Beginning of Period $28.61 $26.85 $25.77 $21.62 $24.92
----------------------------------------------------------------------------------------------
Income From Investment Operations
---------------------------------------
Net Investment Income (Loss)(1) (0.13) (0.05) (0.12) (0.08) -(2)
---------------------------------------
Net Realized and
Unrealized Gain (Loss) (0.37) 1.81 1.20 4.24 (3.30)
----------------------------------------------------------------------------------------------
Total From Investment Operations (0.50) 1.76 1.08 4.16 (3.30)
----------------------------------------------------------------------------------------------
Distributions
---------------------------------------
From Net Investment Income - - - (0.01) -
----------------------------------------------------------------------------------------------
Net Asset Value, End of Period $28.11 $28.61 $26.85 $25.77 $21.62
==============================================================================================
TOTAL RETURN(3) (1.75)% 6.55% 4.19% 19.24% (13.24)%

RATIOS/SUPPLEMENTAL DATA
----------------------------------------------------------------------------------------------
Ratio of Operating Expenses
to Average Net Assets 1.24% 1.24% 1.24% 1.25% 1.24%
---------------------------------------
Ratio of Net Investment Income (Loss)
to Average Net Assets (0.40)% (0.16)% (0.45)% (0.34)% (0.01)%
---------------------------------------
Portfolio Turnover Rate 62% 33% 34% 82% 92%
---------------------------------------
Net Assets, End of Period
(in thousands) $405,173 $639,792 $738,032 $643,144 $391,968
----------------------------------------------------------------------------------------------

(1) COMPUTED USING AVERAGE SHARES OUTSTANDING THROUGHOUT THE PERIOD.

(2) PER-SHARE AMOUNT WAS LESS THAN $0.005.

------
30

NOTES

------
31

NOTES

------
32

NOTES

------
33

MORE INFORMATION ABOUT THE FUND IS CONTAINED IN THESE DOCUMENTS

Annual and Semiannual Reports

Annual and semiannual reports contain more information about the fund's
investments and the market conditions and investment strategies that
significantly affected the fund's performance during the most recent fiscal
period.

Statement of Additional Information (SAI)

The SAI contains a more detailed, legal description of the fund's operations,
investment restrictions, policies and practices. The SAI is incorporated by
reference into this prospectus. This means that it is legally part of this
prospectus, even if you don't request a copy.

You may obtain a free copy of the SAI or annual and semiannual reports, and ask
questions about the fund or your accounts, online at americancentury.com, by
contacting American Century at the addresses or telephone numbers listed below
or by contacting your financial intermediary.

You also can get information about the fund (including the SAI) from the
Securities and Exchange Commission (SEC). The SEC charges a duplicating fee to
provide copies of this information.

IN PERSON SEC Public Reference Room
Washington, D.C.
Call 202-942-8090 for location and hours.

ON THE INTERNET * EDGAR database at sec.gov
* By email request at publicinfo@sec.gov

BY MAIL SEC Public Reference Section
Washington, D.C. 20549-0102

This prospectus shall not constitute an offer to sell securities of the fund in
any state, territory, or other jurisdiction where the fund's shares have not
been registered or qualified for sale, unless such registration or qualification
is not required, or under any circumstances in which such offer or solicitation
would be unlawful.

NEWSPAPER
FUND REFERENCE FUND CODE TICKER LISTING
--------------------------------------------------------------------------------
Ultra Fund
Investor Class 022 TWCUX Ultra
--------------------------------------------------------------------------------
Institutional Class 322 TWUIX Ultra
--------------------------------------------------------------------------------
C Class 422 TWCCX Ultra
--------------------------------------------------------------------------------
R Class 122 AULRX Ultra
--------------------------------------------------------------------------------
Advisor Class 722 TWUAX Ultra
--------------------------------------------------------------------------------

Investment Company Act File No. 811-0816

AMERICAN CENTURY INVESTMENTS
americancentury.com

Banks and Trust Companies, Broker-Dealers,
Self-Directed Retail Investors Financial Professionals, Insurance Companies
P.O. Box 419200 P.O. Box 419786
Kansas City, Missouri 64141-6200 Kansas City, Missouri 64141-6786
1-800-345-2021 or 816-531-5575 1-800-345-6488

0703
SH-PRS-52532

AMERICAN CENTURY INVESTMENTS

Prospectus

March 1, 2007

Growth Fund

THE SECURITIES AND EXCHANGE COMMISSION HAS NOT APPROVED OR DISAPPROVED THESE
SECURITIES OR PASSED UPON THE ADEQUACY OF THIS PROSPECTUS. ANY REPRESENTATION TO
THE CONTRARY IS A CRIMINAL OFFENSE.

American Century Investment
Services, Inc., Distributor

[american century investments logo and text logo]

Table of Contents

AN OVERVIEW OF THE FUND . . . . . . . . . . . . . . . . . . . . .2

FUND PERFORMANCE HISTORY . . . . . . . . . . . . . . . . . . . . 3

FEES AND EXPENSES . . . . . . . . . . . . . . . . . . . . . . . .5

OBJECTIVES, STRATEGIES AND RISKS . . . . . . . . . . . . . . . . 7

MANAGEMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

INVESTING DIRECTLY WITH AMERICAN CENTURY . . . . . . . . . . . .11

INVESTING THROUGH A FINANCIAL INTERMEDIARY . . . . . . . . . . .13

ADDITIONAL POLICIES AFFECTING YOUR INVESTMENT . . . . . . . . . 15

SHARE PRICE AND DISTRIBUTIONS . . . . . . . . . . . . . . . . . 19

TAXES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

MULTIPLE CLASS INFORMATION . . . . . . . . . . . . . . . . . . .23

FINANCIAL HIGHLIGHTS . . . . . . . . . . . . . . . . . . . . . .24

[GRAPHIC OF TRIANGLE]

THIS SYMBOL IS USED THROUGHOUT THE BOOK TO HIGHLIGHT DEFINITIONS OF KEY
INVESTMENT TERMS AND TO PROVIDE OTHER HELPFUL INFORMATION.

American Century Investment Services, Inc., Distributor

The American Century Investments logo, American Century and American Century
Investments are service marks of American Century Proprietary Holdings, Inc.

An Overview of the Fund

WHAT IS THE FUND'S INVESTMENT OBJECTIVE?

The fund seeks long-term capital growth.

WHAT ARE THE FUND'S PRIMARY INVESTMENT STRATEGIES AND PRINCIPAL RISKS?

The portfolio managers look for stocks of companies they believe will increase
in value over time, using an investment strategy developed by American Century.
In implementing this strategy, the portfolio managers make their investment
decisions based primarily on their analysis of individual companies, rather than
on broad economic forecasts. Management of the fund is based on the belief that,
over the long term, stock price movements follow growth in earnings, revenues
and/or cash flow.

-The fund's principal risks include

* GROWTH STOCKS - Investments in growth stocks may involve special risks and
their prices may fluctuate more dramatically than the overall stock market.

* FOREIGN SECURITIES - The fund may invest in foreign securities, which can
be riskier than investing in U.S. securities.

* MARKET RISK - The value of the fund's shares will go up and down based on
the performance of the companies whose securities it owns and other factors
generally affecting the securities market.

* PRICE VOLATILITY - The value of the fund's shares may fluctuate
significantly in the short term.

* PRINCIPAL LOSS - At any given time your shares may be worth less than the
price you paid for them. In other words, it is possible to lose money by
investing in the fund.

A more detailed description of the fund's investment strategies and risks may be
found under the heading OBJECTIVES, STRATEGIES AND RISKS, which begins on page
7.

[GRAPHIC OF TRIANGLE]

AN INVESTMENT IN THE FUND IS NOT A BANK DEPOSIT, AND IT IS NOT INSURED OR
GUARANTEED BY THE FEDERAL DEPOSIT INSURANCE CORPORATION (FDIC) OR ANY OTHER
GOVERNMENT AGENCY.

------
2

FUND PERFORMANCE HISTORY

Annual Total Returns

The following bar chart shows the performance of the fund's Investor Class
shares for each of the last 10 calendar years. It indicates the volatility of
the fund's historical returns from year to year. Account fees and sales charges,
if applicable, are not reflected in the chart below. If they had been included,
returns would be lower than those shown. The returns of the fund's other classes
will differ from those shown in the chart, depending on the expenses of those
classes.

GROWTH FUND - INVESTOR CLASS

The highest and lowest quarterly returns for the periods reflected in the bar
chart are:

HIGHEST LOWEST
--------------------------------------------------------------------------------
Growth 23.62% (4Q 1999) -19.33% (1Q 2001)
--------------------------------------------------------------------------------

Average Annual Total Returns

The benchmark is an unmanaged index that has no operating costs and is included
in each table for performance comparison.

------
3

(1) THE INCEPTION DATE FOR THE INSTITUTIONAL CLASS IS JUNE 16, 1997. ONLY
CLASSES WITH PERFORMANCE HISTORY FOR LESS THAN 10 YEARS SHOW RETURNS FOR
LIFE OF CLASS.

(2) SINCE JUNE 30, 1997, THE DATE CLOSEST TO THE CLASS'S INCEPTION FOR
WHICH DATA IS AVAILABLE.

C CLASS
LIFE OF
FOR THE CALENDAR YEAR ENDED DECEMBER 31, 2006 1 YEAR 5 YEARS CLASS(1)
--------------------------------------------------------------------------------
Return Before Taxes 6.90% 1.71% 1.81%
Russell 1000® Growth Index 9.07% 2.69% 2.61%(2)
(reflects no deduction for
fees, expenses or taxes)
--------------------------------------------------------------------------------

(1) THE INCEPTION DATE FOR THE C CLASS IS NOVEMBER 28, 2001. ONLY CLASSES
WITH PERFORMANCE HISTORY FOR LESS THAN 10 YEARS SHOW RETURNS FOR LIFE OF
CLASS.

(2) SINCE NOVEMBER 30, 2001, THE DATE CLOSEST TO THE CLASS'S INCEPTION FOR
WHICH DATA IS AVAILABLE.

R CLASS

FOR THE CALENDAR YEAR ENDED DECEMBER 31, 2006 1 YEAR LIFE OF CLASS(1)
--------------------------------------------------------------------------------
Return Before Taxes 7.44% 8.80%
Russell 1000® Growth Index 9.07% 9.01%(2)
(reflects no deduction for
fees, expenses or taxes)
--------------------------------------------------------------------------------

(1) THE INCEPTION DATE FOR THE R CLASS IS AUGUST 29, 2003. ONLY CLASSES
WITH PERFORMANCE HISTORY FOR LESS THAN 10 YEARS SHOW RETURNS FOR LIFE OF
CLASS.

(2) SINCE AUGUST 31, 2003, THE DATE CLOSEST TO THE CLASS'S INCEPTION FOR
WHICH DATA IS AVAILABLE.

(1) THE INCEPTION DATE FOR THE ADVISOR CLASS IS JUNE 4, 1997. ONLY CLASSES
WITH PERFORMANCE HISTORY FOR LESS THAN 10 YEARS SHOW RETURNS FOR LIFE OF
CLASS.

(2) SINCE MAY 31, 1997, THE DATE CLOSEST TO THE CLASS'S INCEPTION FOR
WHICH DATA IS AVAILABLE.

Performance information is designed to help you see how fund returns can vary.
Keep in mind that past performance (before and after taxes) does not predict how
a fund will perform in the future.

For current performance information, please call us or visit
americancentury.com.

------
4

FEES AND EXPENSES

There are no sales loads, fees or other charges

* to buy fund shares directly from American Century

* to reinvest dividends in additional shares

* to exchange into the same class of shares of other American Century funds

* to redeem your shares (other than a $10 fee to redeem by wire and the
deferred sales charge associated with C Class shares redeemed during the
first year after purchase)

The following tables describe the fees and expenses you may pay if you buy and
hold shares of the fund.

SHAREHOLDER FEES (FEES PAID DIRECTLY FROM YOUR INVESTMENT)
--------------------------------------------------------------------------------
Investor Class
Maximum Account Maintenance Fee $25(1)
--------------------------------------------------------------------------------
C Class
Maximum Deferred Sales Charge (load) 1.00%(2)
(as a percentage of net asset value)
--------------------------------------------------------------------------------

(2) THE DEFERRED SALES CHARGE IS CONTINGENT ON THE LENGTH OF TIME YOU HAVE
OWNED YOUR SHARES. THE CHARGE IS 1.00% DURING THE FIRST YEAR AFTER PURCHASE
AND IS ELIMINATED THEREAFTER.

ANNUAL FUND OPERATING EXPENSES (EXPENSES THAT ARE DEDUCTED FROM FUND ASSETS)
DISTRIBUTION TOTAL ANNUAL
MANAGEMENT AND SERVICE OTHER FUND OPERATING
FEE(1) (12B-1) FEES(2) EXPENSES(3) EXPENSES
--------------------------------------------------------------------------------
Investor 1.00% None 0.00% 1.00%
Class
--------------------------------------------------------------------------------
Institutional 0.80% None 0.00% 0.80%
Class
--------------------------------------------------------------------------------
C Class 1.00% 1.00% 0.00% 2.00%
--------------------------------------------------------------------------------
R Class 1.00% 0.50% 0.00% 1.50%
--------------------------------------------------------------------------------
Advisor Class 0.75% 0.50% 0.00% 1.25%
--------------------------------------------------------------------------------

(3) OTHER EXPENSES, WHICH INCLUDE THE FEES AND EXPENSES OF THE FUND'S
INDEPENDENT DIRECTORS AND THEIR LEGAL COUNSEL, AS WELL AS INTEREST, WERE
LESS THAN 0.005% FOR THE MOST RECENT FISCAL YEAR.

------
5

EXAMPLE

The examples in the table below are intended to help you compare the costs of
investing in a fund with the costs of investing in other mutual funds. Of
course, your actual costs may be higher or lower. Assuming you . . .

* invest $10,000 in the fund

* redeem all of your shares at the end of the periods shown below

* earn a 5% return each year

* incur the same operating expenses as shown above

. . . your cost of investing in the fund would be:

1 YEAR 3 YEARS 5 YEARS 10 YEARS
--------------------------------------------------------------------------------
Investor Class $102 $318 $551 $1,219
--------------------------------------------------------------------------------
Institutional Class $82 $255 $443 $987
--------------------------------------------------------------------------------
C Class $202 $623 $1,069 $2,305
--------------------------------------------------------------------------------
R Class $152 $472 $814 $1,778
--------------------------------------------------------------------------------
Advisor Class $127 $395 $683 $1,503
--------------------------------------------------------------------------------

------
6

OBJECTIVES, STRATEGIES AND RISKS

WHAT IS THE FUND'S INVESTMENT OBJECTIVE?

The fund seeks long-term capital growth.

HOW DOES THE FUND PURSUE ITS INVESTMENT OBJECTIVE?

Using American Century's extensive computer database, as well as other primary
analytical research tools, the portfolio managers track financial information
for individual companies to identify and evaluate trends in earnings, revenues
and other business fundamentals. Under normal market conditions, the fund's
portfolio will primarily consist of securities of companies demonstrating
business improvement. Analytical indicators helping to identify signs of
business improvement could include accelerating earnings or revenue growth
rates, increasing cash flows, or other indications of the relative strength of a
company's business. These techniques help the portfolio managers buy or hold the
stocks of companies they believe have favorable growth prospects and sell the
stocks of companies whose characteristics no longer meet their criteria.

A description of the policies and procedures with respect to the disclosure of
the fund's portfolio securities is available in the statement of additional
information.

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7

WHAT ARE THE PRINCIPAL RISKS OF INVESTING IN THE FUND?

The portfolio managers may buy a large amount of a company's stock quickly, and
often will dispose of it quickly if the company's earnings or revenues decline.
While the portfolio managers believe this strategy provides substantial
appreciation potential over the long term, in the short term it can create a
significant amount of share price volatility. This volatility can be greater
than that of the average stock fund.

Although the portfolio managers intend to invest the fund's assets primarily in
U.S. stocks, the fund may invest in securities of foreign companies. Foreign
investment involves additional risks, including fluctuations in currency
exchange rates, less stable political and economic structures, reduced
availability of public information, and lack of uniform financial reporting and
regulatory practices similar to those that apply in the United States. These
factors make investing in foreign securities generally riskier than investing in
U.S. stocks. To the extent the fund invests in foreign securities, the overall
risk of that fund could be affected.

Market performance tends to be cyclical, and, in the various cycles, certain
investment styles may fall in and out of favor. If the market is not favoring
the fund's style, the fund's gains may not be as big as, or its losses may be
bigger than, other equity funds using different investment styles.

The value of the fund's shares depends on the value of the stocks and other
securities it owns. The value of the individual securities the fund owns will go
up and down depending on the performance of the companies that issued them,
general market and economic conditions, and investor confidence.

At any given time your shares may be worth less than the price you paid for
them. In other words, it is possible to lose money by investing in the fund.

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8

MANAGEMENT

WHO MANAGES THE FUND?

The Board of Directors, investment advisor and fund management team play key
roles in the management of the fund.

THE BOARD OF DIRECTORS

THE INVESTMENT ADVISOR

The rate of the fee is determined by applying a formula that takes into account
all of the advisor's assets under management in the fund's investment strategy
(strategy assets). Strategy assets include the assets of the fund and the NT
Growth fund as well as certain assets of other clients of the advisor outside
the American Century fund family (such as subadvised funds and separate
accounts) that use very similar investment teams and strategies. The use of
strategy assets, rather than fund assets, in calculating the fund's fee rate
could allow the fund to realize scheduled cost savings more quickly. However, it
is possible that the fund's strategy assets will not include assets of other
client accounts or that any such assets may not be sufficient to result in a
lower fee rate.

MANAGEMENT FEES PAID
BY THE FUND TO THE ADVISOR
AS A PERCENTAGE OF AVERAGE
NET ASSETS FOR THE FISCAL YEAR INVESTOR INSTITUTIONAL C R ADVISOR
ENDED OCTOBER 31, 2006 CLASS CLASS CLASS CLASS CLASS
----------------------------------------------------------------------------------
Growth 1.00% 0.80% 1.00% 1.00% 0.75%
----------------------------------------------------------------------------------

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9

THE FUND MANAGEMENT TEAM

The portfolio managers on the investment team who are jointly and primarily
responsible for the day-to-day management of the fund are identified below.

GREGORY J. WOODHAMS

Mr. Woodhams, Vice President and Senior Portfolio Manager, has been a member of
the team that manages the fund since he joined American Century in September
1997. He has a bachelor's degree in economics from Rice University and an M.A.
in economics from the University of Wisconsin. He is a CFA charterholder.

E. A. PRESCOTT LEGARD

Mr. LeGard, Vice President and Portfolio Manager, has been a member of the team
that manages the fund since March 1999. He has a bachelor's degree in economics
from DePauw University. He is a CFA charterholder.

FUNDAMENTAL INVESTMENT POLICIES

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10

INVESTING DIRECTLY WITH AMERICAN CENTURY

SERVICES AUTOMATICALLY AVAILABLE TO YOU

CONDUCTING BUSINESS IN WRITING

ACCOUNT MAINTENANCE FEE

[GRAPHIC OF TRIANGLE]

PERSONAL ACCOUNTS INCLUDE INDIVIDUAL ACCOUNTS, JOINT ACCOUNTS, UGMA/UTMA
ACCOUNTS, PERSONAL TRUSTS, COVERDELL EDUCATION SAVINGS ACCOUNTS, IRAS (INCLUDING
TRADITIONAL, ROTH, ROLLOVER, SEP-, SARSEP- AND SIMPLE-IRAS), AND CERTAIN OTHER
RETIREMENT ACCOUNTS. IF YOU HAVE ONLY BUSINESS, BUSINESS RETIREMENT,
EMPLOYER-SPONSORED OR AMERICAN CENTURY BROKERAGE ACCOUNTS, YOU ARE CURRENTLY NOT
SUBJECT TO THIS FEE, BUT YOU MAY BE SUBJECT TO OTHER FEES.