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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