The amortized cost and fair value by contractual maturity periods for fixed maturities were as follows at December 31, 2015:

	Amortized		Fair
(In millions)	Cost		Value
Due in one year or less	$	1,397	$	1,403
Due after one year through five years		6,251		6,504
Due after five years through ten years		6,905		7,058
Due after ten years		3,363		3,917
Mortgage and other asset-backed securities		540		573
Total	$	18,456	$	19,455

Actual maturities of these securities could differ from their contractual maturities used in the table above. This could occur because issuers may have the right to call or prepay obligations, with or without penalties, or because in certain cases the Company may have the option to unilaterally extend the contractual maturity date.

Gross unrealized appreciation (depreciation) on fixed maturities by type of issuer is shown below.

(In millions)				December 31, 2015
			Unrealized		Unrealized
	Amortized		Appre-		Depre-		Fair
	Cost		ciation		ciation		Value
Federal government and agency	$	528	$	251	$	-	$	779
State and local government		1,496		147		(2)		1,641
Foreign government		1,870		147		(3)		2,014
Corporate		14,022		632		(206)		14,448
Mortgage-backed		48		2		(1)		49
Other asset-backed		492		39		(7)		524
Total	$	18,456	$	1,218	$	(219)	$	19,455
(In millions)		December 31, 2014
Federal government and agency	$	608	$	346	$	-	$	954
State and local government		1,682		176		(2)		1,856
Foreign government		1,824		121		(5)		1,940
Corporate		12,517		1,014		(33)		13,498
Mortgage-backed		83		3		(1)		85
Other asset-backed		564		87		(1)		650
Total	$	17,278	$	1,747	$	(42)	$	18,983

The above table includes investments with a fair value of $2.7 billion at December 31, 2015 and $3.1 billion at December 31, 2014 supporting liabilities of the Company's run-off settlement annuity business. These investments had gross unrealized appreciation of $521 million and gross unrealized depreciation of $38 million at December 31, 2015, compared with gross unrealized appreciation of $758 million and gross unrealized depreciation of $2 million at December 31, 2014. Such unrealized amounts are reported in future policy benefit liabilities rather than accumulated other comprehensive income.

As of December 31, 2015, the Company had commitments to purchase $15 million of fixed maturities, all of which bear interest at a fixed market rate.

Review of declines in fair value. Management reviews fixed maturities with a decline in fair value from cost for impairment based on criteria that include:

The table below summarizes fixed maturities with a decline in fair value from amortized cost as of December 31, 2015 but with no indicative impairment loss based on the criteria listed above. These fixed maturities are primarily corporate securities with a decline in fair value that reflects an increase in market yields since purchase.

(Dollars in millions)	December 31, 2015
	Fair		Amortized		Unrealized		Number
	Value		Cost		Depreciation		of Issues
Fixed maturities:
One year or less:
Investment grade	$	4,411	$	4,558	$	(147)	721
Below investment grade	$	534	$	557	$	(23)	228
More than one year:
Investment grade	$	180	$	204	$	(24)	56
Below investment grade	$	124	$	149	$	(25)	29

There were no available for sale equity securities with a significant unrealized loss reflected in accumulated other comprehensive income at December 31, 2015. Equity securities include hybrid investments consisting of preferred stock with call features that are carried at fair value with changes in fair value reported in other realized investment gains (losses) and dividends reported in net investment income. As of December 31, 2015, fair values of these securities were $52 million and amortized cost was $66 million. As of December 31, 2014, fair values of these securities were $57 million and amortized cost was $69 million.

Mortgage loans held by the Company are made exclusively to commercial borrowers and are diversified by property type, location and borrower. Loans are generally issued at a fixed rate of interest and are secured by high quality, primarily completed and substantially leased operating properties.

At December 31, commercial mortgage loans were distributed among the following property types and geographic regions:

(In millions)	2015		2014
Property type
Office buildings	$	697	$	700
Apartment buildings		366		264
Industrial		322		466
Hotels		259		351
Retail facilities		213		272
Other		7		28
Total	$	1,864	$	2,081
Geographic region
Pacific	$	738	$	637
South Atlantic		366		572
New England		276		277
Central		205		214
Middle Atlantic		227		287
Mountain		52		94
Total	$	1,864	$	2,081

At December 31, 2015, scheduled commercial mortgage loan maturities were as follows (in millions): $205 in 2016, $143 in 2017, $177 in 2018, $275 in 2019 and $1,064 thereafter. Actual maturities could differ from contractual maturities for several reasons: borrowers may have the right to prepay obligations with or without prepayment penalties; the maturity date may be extended; and loans may be refinanced.

As of December 31, 2015, the Company had commitments to extend credit under commercial mortgage loan agreements of $5 million.

Credit quality. The Company regularly evaluates and monitors credit risk, beginning with the initial underwriting of a mortgage loan and continuing throughout the investment holding period. Mortgage origination professionals employ an internal credit quality rating system designed to evaluate the relative risk of the transaction at origination that is then updated each year as part of the annual portfolio loan review. The Company evaluates and monitors credit quality on an ongoing basis, classifying each loan as a loan in good standing, potential problem loan or problem loan.

Quality ratings are based on our evaluation of a number of key inputs related to the loan, including real estate market-related factors such as rental rates and vacancies, and property-specific inputs such as growth rate assumptions and lease rollover statistics. However, the two most significant contributors to the credit quality rating are the debt service coverage and loan-to-value ratios. The debt service coverage ratio measures the amount of property cash flow available to meet annual interest and principal payments on debt, with a ratio below 1.0 indicating that there is not enough cash flow to cover the required loan payments. The loan-to-value ratio, commonly expressed as a percentage, compares the amount of the loan to the fair value of the underlying property collateralizing the loan.

The following tables summarize the credit risk profile of the Company's commercial mortgage loan portfolio based on loan-to-value and debt service coverage ratios, as of December 31, 2015 and 2014:

(In millions)	Debt Service Coverage Ratio
				December 31, 2015
		1.30x or		1.20x to		1.10x to		1.00x to		Less than
Loan-to-Value Ratios		Greater		1.29x		1.19x		1.09x		1.00x		Total
Below 50%	$	261	$	2	$	-	$	67	$	-	$	330
50% to 59%		683		-		-		24		-		707
60% to 69%		590		14		-		19		-		623
70% to 79%		-		-		-		30		36		66
80% to 89%		40		-		-		-		-		40
90% to 100%		-		-		-		-		98		98
Total	$	1,574	$	16	$	-	$	140	$	134	$	1,864
	December 31, 2014
Below 50%	$	340	$	17	$	-	$	6	$	-	$	363
50% to 59%		681		38		-		-		-		719
60% to 69%		394		-		15		-		60		469
70% to 79%		68		36		33		-		80		217
80% to 89%		6		41		-		-		58		105
90% to 100%		-		-		55		-		153		208
Total	$	1,489	$	132	$	103	$	6	$	351	$	2,081

The Company's annual in-depth review of its commercial mortgage loan investments is the primary mechanism for identifying emerging risks in the portfolio. The most recent review was completed by the Company's investment professionals in the second quarter of 2015 and included an analysis of each underlying property's most recent annual financial statements, rent rolls, operating plans, budgets for 2015, a physical inspection of the property and other pertinent factors. Based on historical results, current leases, lease expirations and rental conditions in each market, the Company estimates the current year and future stabilized property income and fair value, and categorizes the investments as loans in good standing, potential problem loans or problem loans. Based on property valuations and cash flows estimated as part of this review, and considering updates for loans where material changes were subsequently identified, the portfolio's average loan-to-value ratio improved to 58% at December 31, 2015 from 63% at December 31, 2014. The portfolio's average debt service coverage ratio was estimated to be 1.78 at December 31, 2015, an improvement from 1.66 at December 31, 2014.

The Company will reevaluate a loan's credit quality between annual reviews if new property information is received or an event such as delinquency or a borrower's request for restructure causes management to believe that the Company's estimate of financial performance, fair value or the risk profile of the underlying property has been impacted.

Certain loans were modified during 2015 and 2014. However, these were not considered troubled debt restructures and the impact of such modifications was not material to the Company's results of operations, financial condition or liquidity.

Potential problem mortgage loans are considered current (no payment is more than 59 days past due), but exhibit certain characteristics that increase the likelihood of future default such as the deterioration of debt service coverage below 1.0, estimated loan-to-value ratios increasing to 100% or more, downgrade in quality rating and requests from the borrower for restructuring. In addition, loans are considered potential problems if principal or interest payments are past due by more than 30 but less than 60 days. Problem mortgage loans are either in default by 60 days or more or have been restructured as to terms, which could include concessions on interest rate, principal payment or maturity date. The Company monitors each problem and potential problem mortgage loan on an ongoing basis and updates the loan categorization and quality rating when warranted.

Problem and potential problem mortgage loans, net of valuation reserves, totaled $139 million at December 31, 2015 and $208 million at December 31, 2014.

Impaired commercial mortgage loans. The carrying value of the Company's impaired commercial mortgage loans and related valuation reserves were as follows:

(In millions)		2015					2014
		Gross		Reserves		Net		Gross		Reserves		Net
Impaired commercial mortgage loans with valuation reserves	$	113	$	(15)	$	98	$	147	$	(12)	$	135
Impaired commercial mortgage loans with no valuation reserves		-		-		-		31		-		31
Total	$	113	$	(15)	$	98	$	178	$	(12)	$	166

The average recorded investment in impaired loans was $126 million during 2015 and $155 million during 2014. Because of the risk profile of the underlying investment, the Company recognizes interest income on problem mortgage loans only when payment is actually received. Interest income that would have been reflected in net income if interest on non-accrual commercial mortgage loans had been accrued in accordance with the original terms was not significant for 2015 or 2014. Interest income on impaired commercial mortgage loans was not significant for 2015 or 2014. See Note 2 for further information on impaired commercial mortgage loans.

Changes in valuation reserves for commercial mortgage loans were not material for the years ended December 31, 2015 and 2014.

Real estate investments and securities partnerships with a carrying value of $277 million at December 31, 2015 and $264 million at December 31, 2014 were non-income producing during the preceding twelve months.

The Company expects to disburse approximately 40% of the committed amounts in 2016.

Short-term investments and cash equivalents included corporate securities of $925 million, federal government securities of $220 million and money market funds of $55 million as of December 31, 2015. The Company's short-term investments and cash equivalents as of December 31, 2014 included corporate securities of $509 million, federal government securities of $274 million and money market funds of $33 million.

As of December 31, 2015 and 2014, the Company did not have a concentration of investments in a single issuer or borrower exceeding 10% of shareholders' equity.