Exhibit 99.1

FOR IMMEDIATE RELEASE

ALLIED WORLD REPORTS RECORD 2009 RESULTS; GROWS BOOK VALUE BY 33%

PEMBROKE, BERMUDA, February 11, 2010 — Allied World Assurance Company Holdings, Ltd (NYSE: AWH) today reported net income of $161.3 million, or $3.05 per diluted share, for the fourth quarter of 2009 compared to net income of $19.9 million, or $0.39 per diluted share, for the fourth quarter of 2008. Net income for the year ended December 31, 2009 was a record $606.9 million, or $11.67 per diluted share, compared to net income of $183.6 million, or $3.59 per diluted share, for the year ended December 31, 2008.

The company reported operating income of $131.9 million, or $2.49 per diluted share, for the fourth quarter of 2009 compared to operating income of $141.1 million, or $2.80 per diluted share, for the fourth quarter of 2008. Operating income for the year ended December 31, 2009 was a record $537.7 million, or $10.34 per diluted share, compared to operating income of $455.1 million, or $8.90 per diluted share, for the year ended December 31, 2008.

President and Chief Executive Officer Scott Carmilani commented, “Despite the challenging market environment, I am very pleased to report exceptional results to our shareholders for the fourth quarter and full year 2009. Net income for 2009 exceeded $600 million for the first time in our company’s history and our operating return on shareholders’ equity was a very impressive 20% for the year. Our shareholders’ equity base has grown to $3.2 billion, which is up 33% from the beginning of the year.”

Underwriting Results

Gross premiums written were $322.1 million in the fourth quarter of 2009, a 3.6% increase compared to $310.9 million in the fourth quarter of 2008. For the year ended December 31, 2009, gross premiums written totaled $1,696.3 million, a 17.3% increase compared to $1,445.6 million for the year ended December 31, 2008. Net premiums written were $233.7 million in the fourth quarter of 2009, a 3.2% increase compared to $226.5 million in the fourth quarter of 2008. For the year ended December 31, 2009, net premiums written totaled $1,321.1 million, a 19.3% increase compared to $1,107.2 million for the year ended December 31, 2008. These increases were primarily due to the expansion of our U.S. insurance business offset by our selectively paring back general property, energy and professional liability risk in our international insurance segment that did not meet our underwriting requirements.

Net premiums earned in the fourth quarter of 2009 were $330.5 million, a 9.1% increase compared to $303.0 million in the fourth quarter of 2008. For the year ended December 31, 2009, net premiums earned totaled $1,316.9 million, a 17.9% increase from net premiums earned of $1,116.9 million for the year ended December 31, 2008. These increases were primarily due to the expansion of our U.S. insurance business.

The combined ratio was 76.2% in the fourth quarter of 2009 compared to 75.9% in the fourth quarter of 2008. The loss and loss expense ratio was 42.8% in the fourth quarter of 2009 compared to 47.4% in the fourth quarter of 2008. During the fourth quarter of 2009, the company recorded net favorable reserve development on prior loss years of $77.7 million, a benefit of 23.5 percentage points to the company’s loss and loss expense ratio for the quarter. This compares to the fourth quarter of 2008, where the company recorded net favorable reserve development on prior loss years of $90.3 million, a benefit of 29.8 percentage points to the company’s loss and loss expense ratio for that quarter. Absent prior year reserve adjustments, the loss and loss expense ratio related to the fourth quarter of 2009 was 66.3% compared to 77.2% for the fourth quarter of 2008. During the three months ended December 31 2008, the company added $41.7 million to its reserves related to Hurricanes Ike and Gustav.

For the year ended December 31, 2009, the combined ratio was 76.1% compared to 84.1% for the year ended December 31, 2008. For the year ended December 31, 2009, the company recorded net favorable reserve development on prior loss years of $248.0 million, a benefit of 18.8 percentage points to the company’s loss and loss expense ratio. For the year ended December 31, 2008, the company recorded net favorable reserve development on prior loss years of $280.1 million, a benefit of 25.1 percentage points to the company’s loss and loss expense ratio.

The company’s reported expense ratio was 33.4% and 30.2% for the fourth quarter and full year 2009, respectively. These ratios were impacted by 3.6 percentage points and 0.9 percentage points for the fourth quarter and full year 2009, respectively, due to the company recording $11.8 million related to our reaching certain incentive based performance hurdles. Absent this item, the company’s expense ratios would have been 29.8% and 29.3% for the fourth quarter and full year 2009, respectively, which compare to the company’s expense ratios for the fourth quarter and full year 2008 of 28.5% and 26.7%, respectively. Our overall staff count increased to over 650 as of December 31, 2009 from 560 as of December 31, 2008, primarily driven by the additional staff in our U.S. insurance operations. As a result of the increased staff count, salary and employee welfare costs increased by $4.3 million and $48.3 million during the fourth quarter and year ended December 31, 2009, respectively.

Amortization and Impairment of Intangible Assets

At the end of 2009, we made a strategic decision to market all products, with a few limited exceptions, under the Allied World brand instead of under the Darwin Professional Underwriters, Inc. (“Darwin”) brand. We believe that Darwin related business will benefit from greater access to markets under the Allied World brand, which is a more internationally recognized brand. Accordingly, an impairment charge of $6.9 million was incurred to write off the unamortized balance of the trademark intangible asset acquired as part of the October 2008 acquisition of Darwin.

Investment Results

Net investment income in the fourth quarter of 2009 was $73.3 million, a decrease of 11.3% from the $82.6 million of net investment income in the fourth quarter of 2008. The primary reason for the decrease was that in the fourth quarter of 2008 the company received a $7.9 million dividend from a high-yield bond fund. For the year ended December 31, 2009, net investment income was $300.7 million, a decrease of 2.6% from the $308.8 million of net investment income for the year ended December 31, 2008.

The company recorded net realized investment gains of $37.8 million and $126.4 million for the three months and year ended December 31, 2009, respectively. As of December 31, 2009 and December 31, 2008, net accumulated unrealized gains were $149.8 million and $105.6 million, respectively. The increase in net unrealized investment gains from December 31, 2008 to December 31, 2009 was due to unrealized gains in our fixed-maturity portfolio of $181.1 million primarily resulting from the narrowing of credit spreads across all fixed income classes partially offset by the cumulative effect adjustment of $136.8 million related to the company adopting accounting changes for investments in the second quarter of 2009.

Shareholders’ Equity

As of December 31, 2009, shareholders’ equity was $3.2 billion, an increase of 33% compared to $2.4 billion reported as of December 31, 2008. The increase was primarily due to strong underwriting results, prudent investment decisions and benign catastrophe activity.

The company’s annualized net income return on average shareholders’ equity for the three months and year ended December 31, 2009 was 21.7% and 22.6%, respectively. The company’s annualized operating return on average shareholders’ equity for the three months and year ended December 31, 2009 was 17.7% and 20.0%, respectively.

As of December 31, 2009, diluted book value per share was $59.56, an increase of 29.3% compared to $46.05 as of December 31, 2008.

Investment Supplement

Allied World will be providing additional information on its investment portfolio as of December 31, 2009. This information will be available at the “Investor Relations” section of the company’s website at www.awac.com.

Financial Supplement

A financial supplement relating to the fourth quarter of 2009 will be available at the “Investor Relations” section of the company’s website at www.awac.com.

Conference Call

Allied World will host a conference call on Friday, February 12, 2010 at 8:30 a.m. (Eastern Time) to discuss its fourth quarter and year ended December 31, 2009 financial results. The public may access a live webcast of the conference call at the “Investor Relations” section of the company’s website at www.awac.com. In addition, the conference call can be accessed by dialing (866) 713-8310 (U.S. and Canada callers) or (617) 597-5308 (international callers) and entering the passcode 11691912 approximately ten minutes prior to the call.

Following the conclusion of the presentation, a replay of the call will be available through Friday, February 26, 2010 by dialing (888) 286-8010 (U.S. and Canada callers) or (617) 801-6888 (international callers) and entering the passcode 80525762. In addition, the webcast will remain available online through Friday, February 26, 2010 at www.awac.com.

Non-GAAP Financial Measures

In presenting the company’s results, management has included and discussed in this press release certain non generally accepted accounting principles (“non-GAAP”) financial measures within the meaning of Regulation G as promulgated by the U.S. Securities and Exchange Commission. Management believes that these non-GAAP measures, which may be defined differently by other companies, better explain the company’s results of operations in a manner that allows for a more complete understanding of the underlying trends in the company’s business. However, these measures should not be viewed as a substitute for those determined in accordance with generally accepted accounting principles (“GAAP”).

“Operating income” is an internal performance measure used by the company in the management of its operations and represents after-tax operational results excluding, as applicable, net realized investment gains or losses, net impairment charges recognized in earnings and foreign exchange gain or loss. The company excludes net realized investment gains or losses, net impairment charges recognized in earnings and net foreign exchange gain or loss from its calculation of operating income because the amount of these gains or losses is heavily influenced by, and fluctuates in part according to, the availability of market opportunities. The company believes these amounts are largely independent of its business and underwriting process and including them may distort the analysis of trends in its insurance and reinsurance operations. In addition to presenting net income determined in accordance with GAAP, the company believes that showing operating income enables investors, analysts, rating agencies and other users of its financial information to more easily analyze the company’s results of operations in a manner similar to how management analyzes the company’s underlying business performance. Operating income should not be viewed as a substitute for GAAP net income.

The company has included “diluted book value per share” because it takes into account the effect of dilutive securities; therefore, the company believes it is a better measure of calculating shareholder returns than book value per share.

“Annualized net income return on average shareholders’ equity” (“ROAE”) is calculated using average shareholders’ equity, excluding the average after tax unrealized gains or losses on investments. Unrealized gains (losses) on investments are primarily the result of interest rate and risk premium movements and the resultant impact on fixed income securities. Such gains (losses) are not related to management actions or operational performance, nor are they likely to be realized. Therefore, the company believes that excluding these unrealized gains (losses) provides a more consistent and useful measurement of operating performance, which supplements GAAP information. In calculating ROAE, the net income (loss) available to shareholders for the period is multiplied by the number of such periods in a calendar year in order to arrive at annualized net income (loss) available to shareholders. The company presents ROAE as a measure that is commonly recognized as a standard of performance by investors, analysts, rating agencies and other users of its financial information.

“Annualized operating return on average shareholders’ equity” is calculated using operating income (as defined above and annualized in the manner described for net income (loss) available to shareholders under ROAE above), and average shareholders’ equity, excluding the average after tax unrealized gains (losses) on investments. Unrealized gains (losses) are excluded from equity for the reasons outlined in the annualized net income return on average shareholders’ equity explanation above.

Reconciliations of these financial measures to their most directly comparable GAAP measures are included in the attached tables.

About Allied World Assurance Company

Allied World Assurance Company Holdings, Ltd, through its subsidiaries, is a global provider of innovative property, casualty and specialty insurance and reinsurance solutions, offering superior client service through offices in Bermuda, Europe, Hong Kong, Singapore and the United States. Our insurance and reinsurance subsidiaries are rated A (Excellent) by A.M. Best Company. For further information on Allied World, please visit our website at www.awac.com.

Cautionary Statement Regarding Forward-Looking Statements

Any forward-looking statements made in this press release reflect our current views with respect to future events and financial performance and are made pursuant to the safe harbor provisions of the Private Securities Litigation Reform Act of 1995. Such statements involve risks and uncertainties, which may cause actual results to differ materially from those set forth in these statements. For example, our forward-looking statements could be affected by pricing and policy term trends; increased competition; the impact of acts of terrorism and acts of war; greater frequency or severity of unpredictable catastrophic events; investigations of market practices and related settlement terms; negative rating agency actions; the adequacy of our loss reserves; the company or its subsidiaries becoming subject to significant income taxes in the United States or elsewhere; changes in regulations or tax laws; changes in the availability, cost or quality of reinsurance or retrocessional coverage; adverse general economic conditions including those related to the ongoing financial crisis; and judicial, legislative, political and other governmental developments, as well as management’s response to these factors, and other factors identified in our filings with the U.S. Securities and Exchange Commission. You are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date on which they are made. We are under no obligation (and expressly disclaim any such obligation) to update or revise any forward-looking statement that may be made from time to time, whether as a result of new information, future developments or otherwise.

ALLIED WORLD ASSURANCE COMPANY HOLDINGS, LTD
UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS
(Expressed in thousands of United States dollars, except share and per share amounts)

	Quarter Ended December 31,						Year Ended December 31,
	2009			2008			2009			2008
Revenues:
Gross premiums written	$	322,129		$	310,945		$	1,696,345		$	1,445,584
Premiums ceded		(88,435	)		(84,442	)		(375,220	)		(338,356	)
Net premiums written		233,694			226,503			1,321,125			1,107,228
Change in unearned premiums		96,787			76,481			(4,233	)		9,677
Net premiums earned		330,481			302,984			1,316,892			1,116,905
Net investment income		73,252			82,583			300,675			308,775
Net realized investment gains (losses)		37,796			(19,454	)		126,352			(59,954	)
Net impairment charges recognized in earnings		(187	)		(100,593	)		(49,577	)		(212,897	)
Other income		373			746			1,506			746
Total revenue		441,715			266,266			1,695,848			1,153,575
Expenses:
Net losses and loss expenses		141,403			143,531			604,060			641,122
Acquisition costs		38,126			30,849			148,847			112,569
General and administrative expenses		72,212			55,405			248,592			185,850
Amortization and impairment of intangible assets		7,856			710			11,051			710
Interest expense		9,527			10,205			39,019			38,743
Foreign exchange loss (gain)		1,408			1,230			748			(1,421	)
Total expenses		270,532			241,930			1,052,317			977,573
Income before income taxes		171,183			24,336			643,531			176,002
Income tax expense (recovery)		9,928			4,484			36,644			(7,633	)
NET INCOME	$	161,255		$	19,852		$	606,887		$	183,635
PER SHARE DATA:
Basic earnings per share	$	3.25		$	0.40		$	12.26		$	3.75
Diluted earnings per share	$	3.05		$	0.39		$	11.67		$	3.59
Weighted average common shares outstanding		49,662,575			49,028,249			49,503,438			48,936,912
Weighted average common shares and common share equivalents outstanding		52,880,733			50,366,814			51,992,674			51,147,215
Dividends declared per share	$	0.20		$	0.18		$	0.74		$	0.72

ALLIED WORLD ASSURANCE COMPANY HOLDINGS, LTD
UNAUDITED CONDENSED CONSOLIDATED BALANCE SHEETS
(Expressed in thousands of United States dollars, except share and per share amounts)

	As of		As of
	December 31,		December 31,
	2009		2008
ASSETS:
Fixed maturity investments available for sale, at fair value (amortized cost: 2009: $4,260,844; 2008: $5,872,031)	$	4,427,072	$	6,032,029
Fixed maturity investments trading, at fair value		2,544,322		—
Other invested assets trading, at fair value		184,869		69,902
Other invested assets available for sale, at fair value (cost: 2009: nil; 2008: $89,229)		—		55,199
Total investments		7,156,263		6,157,130
Cash and cash equivalents		379,751		706,267
Securities lending collateral		—		171,026
Insurance balances receivable		395,621		347,941
Prepaid reinsurance		186,610		192,582
Reinsurance recoverable		919,991		888,314
Accrued investment income		53,046		50,671
Net deferred acquisition costs		87,821		86,181
Goodwill		268,376		268,532
Intangible assets		60,359		71,410
Net balances receivable on purchases and sales of investments		184		12,371
Net deferred tax assets		21,895		22,452
Other assets		67,566		47,603
Total assets	$	9,597,483	$	9,022,480
LIABILITIES:
Reserve for losses and loss expenses	$	4,761,772	$	4,576,828
Unearned premiums		928,619		930,358
Reinsurance balances payable		102,837		95,129
Securities lending payable		—		177,010
Syndicated loan		—		243,750
Senior notes		498,919		498,796
Accounts payable and accrued liabilities		92,041		83,747
Total liabilities	$	6,384,188	$	6,605,618
SHAREHOLDERS’ EQUITY:
Common shares, par value $0.03 per share: issued and outstanding 2009: 49,734,487; 2008: 49,036,159 shares	$	1,492	$	1,471
Additional paid-in capital		1,359,934		1,314,785
Retained earnings		1,702,020		994,974
Accumulated other comprehensive income, net of tax		149,849		105,632
Total shareholders’ equity	$	3,213,295	$	2,416,862
Total liabilities and shareholders’ equity	$	9,597,483	$	9,022,480

ALLIED WORLD ASSURANCE COMPANY HOLDINGS, LTD
UNAUDITED CONSOLIDATED SEGMENT DATA
(Expressed in thousands of United States dollars, except for ratio information)

	U.S.			International
Quarter Ended December 31, 2009	Insurance			Insurance			Reinsurance			Total
Gross premiums written	$	169,116		$	130,272		$	22,741		$	322,129
Net premiums written		123,155			87,827			22,712			233,694
Net premiums earned		119,641			92,464			118,376			330,481
Other income		373			—			—			373
Net losses and loss expenses		(68,273	)		(16,467	)		(56,663	)		(141,403	)
Acquisition costs		(15,806	)		501			(22,821	)		(38,126	)
General and administrative expenses		(32,474	)		(25,791	)		(13,947	)		(72,212	)
Underwriting income		3,461			50,707			24,945			79,113
Net investment income											73,252
Net realized investment gains											37,796
Net impairment charges recognized in earnings											(187	)
Amortization and impairment of intangible assets											(7,856	)
Interest expense											(9,527	)
Foreign exchange loss											(1,408	)
Income before income taxes										$	171,183
GAAP Ratios:
Loss and loss expense ratio		57.1	%		17.8	%		47.9	%		42.8	%
Acquisition cost ratio		13.2	%		(0.5	%)		19.3	%		11.5	%
General and administrative expense ratio		27.1	%		27.9	%		11.8	%		21.9	%
Combined ratio		97.4	%		45.2	%		79.0	%		76.2	%

	U.S.			International
Quarter Ended December 31, 2008	Insurance			Insurance			Reinsurance			Total
Gross premiums written	$	153,671		$	147,025		$	10,249		$	310,945
Net premiums written		108,541			107,833			10,129			226,503
Net premiums earned		86,060			115,434			101,490			302,984
Other income		746			—			—			746
Net losses and loss expenses		(34,572	)		(47,136	)		(61,823	)		(143,531	)
Acquisition costs		(9,363	)		(1,525	)		(19,961	)		(30,849	)
General and administrative expenses		(27,359	)		(16,399	)		(11,647	)		(55,405	)
Underwriting income		15,512			50,374			8,059			73,945
Net investment income											82,583
Net realized investment losses											(19,454	)
Net impairment charges recognized in earnings											(100,593	)
Amortization and impairment of intangible assets											(710	)
Interest expense											(10,205	)
Foreign exchange loss											(1,230	)
Income before income taxes										$	24,336
GAAP Ratios:
Loss and loss expense ratio		40.2	%		40.8	%		60.9	%		47.4	%
Acquisition cost ratio		10.9	%		1.3	%		19.7	%		10.2	%
General and administrative expense ratio		31.8	%		14.2	%		11.5	%		18.3	%
Combined ratio		82.9	%		56.3	%		92.1	%		75.9	%

ALLIED WORLD ASSURANCE COMPANY HOLDINGS, LTD
UNAUDITED CONSOLIDATED SEGMENT DATA
(Expressed in thousands of United States dollars, except for ratio information)

	U.S.			International
Year Ended December 31, 2009	Insurance			Insurance			Reinsurance			Total
Gross premiums written	$	674,826		$	555,944		$	465,575		$	1,696,345
Net premiums written		493,067			362,893			465,165			1,321,125
Net premiums earned		447,491			413,170			456,231			1,316,892
Other income		1,506			—			—			1,506
Net losses and loss expenses		(211,363	)		(158,062	)		(234,635	)		(604,060	)
Acquisition costs		(58,114	)		(2,742	)		(87,991	)		(148,847	)
General and administrative expenses		(115,797	)		(84,390	)		(48,405	)		(248,592	)
Underwriting income		63,723			167,976			85,200			316,899
Net investment income											300,675
Net realized investment gains											126,352
Net impairment charges recognized in earnings											(49,577	)
Amortization and impairment of intangible assets											(11,051	)
Interest expense											(39,019	)
Foreign exchange loss											(748	)
Income before income taxes										$	643,531
GAAP Ratios:
Loss and loss expense ratio		47.2	%		38.3	%		51.4	%		45.9	%
Acquisition cost ratio		13.0	%		0.7	%		19.3	%		11.3	%
General and administrative expense ratio		25.9	%		20.4	%		10.6	%		18.9	%
Combined ratio		86.1	%		59.4	%		81.3	%		76.1	%

	U.S.			International
Year Ended December 31, 2008	Insurance			Insurance			Reinsurance			Total
Gross premiums written	$	319,985		$	695,459		$	430,140		$	1,445,584
Net premiums written		212,978			465,869			428,381			1,107,228
Net premiums earned		179,818			472,550			464,537			1,116,905
Other income		746			—			—			746
Net losses and loss expenses		(103,363	)		(288,620	)		(249,139	)		(641,122	)
Acquisition costs		(17,832	)		(3,774	)		(90,963	)		(112,569	)
General and administrative expenses		(66,810	)		(75,490	)		(43,550	)		(185,850	)
Underwriting (loss) income		(7,441	)		104,666			80,885			178,110
Net investment income											308,775
Net realized investment losses											(59,954	)
Net impairment charges recognized in earnings											(212,897	)
Amortization and impairment of intangible assets											(710	)
Interest expense											(38,743	)
Foreign exchange gain											1,421
Income before income taxes										$	176,002
GAAP Ratios:
Loss and loss expense ratio		57.5	%		61.1	%		53.6	%		57.4	%
Acquisition cost ratio		9.9	%		0.8	%		19.6	%		10.1	%
General and administrative expense ratio		37.2	%		16.0	%		9.4	%		16.6	%
Combined ratio		104.6	%		77.9	%		82.6	%		84.1	%

ALLIED WORLD ASSURANCE COMPANY HOLDINGS, LTD
UNAUDITED OPERATING INCOME RECONCILIATION
(Expressed in thousands of United States dollars, except share and per share amounts)

	Quarter Ended December 31,					Year Ended December 31,
	2009			2008		2009			2008
Net income	$	161,255		$	19,852	$	606,887		$	183,635
Net realized investment (gains) losses		(37,796	)		19,454		(126,352	)		59,954
Net impairment charges recognized in earnings		187			100,593		49,577			212,897
Impairment of intangible assets		6,866			—		6,866			—
Foreign exchange loss (gain)		1,408			1,230		748			(1,421	)
Operating income	$	131,920		$	141,129	$	537,726		$	455,065
Weighted average common shares outstanding:
Basic		49,662,575			49,028,249		49,503,438			48,936,912
Diluted		52,880,733			50,366,814		51,992,674			51,147,215
Basic per share data:
Net income	$	3.25		$	0.40	$	12.26		$	3.75
Net realized investment (gains) losses		(0.76	)		0.40		(2.55	)		1.23
Net impairment charges recognized in earnings		—			2.05		1.00			4.35
Impairment of intangible assets		0.14			—		0.14			—
Foreign exchange loss (gain)		0.03			0.03		0.01			(0.03	)
Operating income	$	2.66		$	2.88	$	10.86		$	9.30
Diluted per share data
Net income	$	3.05		$	0.39	$	11.67		$	3.59
Net realized investment (gains) losses		(0.72	)		0.39		(2.43	)		1.17
Net impairment charges recognized in earnings		—			2.00		0.96			4.16
Impairment of intangible assets		0.13			—		0.13			—
Foreign exchange loss (gain)		0.03			0.02		0.01			(0.02	)
Operating income	$	2.49		$	2.80	$	10.34		$	8.90

ALLIED WORLD ASSURANCE COMPANY HOLDINGS, LTD
UNAUDITED DILUTED BOOK VALUE PER SHARE RECONCILIATION
(Expressed in thousands of United States dollars, except share and per share amounts)

	As of			As of
	December 31,			December 31,
	2009			2008
Price per share at period end	$	46.07		$	40.60
Total shareholders’ equity		3,213,295			2,416,862
Basic common shares outstanding		49,734,487			49,036,159
Add: unvested restricted share units		915,432			971,907
Add: Performance based equity awards		1,583,237			1,345,903
Add: dilutive options/warrants outstanding		6,805,157			6,371,151
Weighted average exercise price per share		34.44			33.38
Deduct: options bought back via treasury method		(5,087,405	)		(5,237,965	)
Common shares and common share equivalents outstanding		53,950,908			52,487,155
Basic book value per common share	$	64.61		$	49.29
Diluted book value per common share	$	59.56		$	46.05

ALLIED WORLD ASSURANCE COMPANY HOLDINGS, LTD
UNAUDITED ANNUALIZED RETURN ON SHAREHOLDERS’ EQUITY RECONCILIATION
(Expressed in thousands of United States dollars, except for percentage information)

	Quarter Ended December 31,						Year Ended December 31,
	2009			2008			2009			2008
Opening shareholders’ equity	$	3,078,894		$	2,272,828		$	2,416,862		$	2,239,842
Deduct/Add: accumulated other comprehensive (income) loss		(185,043	)		19,775			(105,632	)		(136,214	)
Adjusted opening shareholders’ equity		2,893,851			2,292,603			2,311,230			2,103,628
Closing shareholders’ equity	$	3,213,295		$	2,416,862		$	3,213,295		$	2,416,862
Deduct: accumulated other comprehensive income		(149,849	)		(105,632	)		(149,849	)		(105,632	)
Adjusted closing shareholders’ equity		3,063,446			2,311,230			3,063,446			2,311,230
Average shareholders’ equity	$	2,978,649		$	2,301,917		$	2,687,338		$	2,207,429
Net income available to shareholders	$	161,255		$	19,852		$	606,887		$	183,635
Annualized net income available to shareholders		645,020			79,408			606,887			183,635
Annualized return on average shareholders’ equity — net income available to shareholders		21.7	%		3.4	%		22.6	%		8.3	%
Operating income available to shareholders	$	131,920		$	141,129		$	537,726		$	455,065
Annualized operating income available to shareholders		527,680			564,516			537,726			455,065
Annualized return on average shareholders’ equity — operating income available to shareholders		17.7	%		24.5	%		20.0	%		20.6	%

SOURCE Allied World Assurance Company Holdings, Ltd

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