Alterra Capital 8-K Alterra Capital Reports First Quarter 2011 Results

Exhibit 99.2

ALTERRA CAPITAL HOLDINGS LIMITED

Investor Financial Supplement

First Quarter 2011

(Unaudited)

This supplement is for information purposes only. It should be read in conjunction with documents filed by Alterra Capital

Holdings Limited with the U.S. Securities and Exchange Commission pursuant to the Securities Exchange Act 1934.

Alterra Capital Holdings Limited

Investors:

Susan Spivak Bernstein, +1-212-898-6640

or

Media:

Kekst and Company

Roanne Kulakoff or Peter Hill, +1-212-521-4800

ALTERRA CAPITAL HOLDINGS LIMITED

Cautionary note regarding forward-looking information

This financial supplement may include forward-looking statements that reflect Alterra’s current views with respect to future events and financial performance. Statements that include the words “expect,” “intend,” “plan,” “believe,” “project,” “anticipate,” “will,” “may” and similar statements of a future or forward-looking nature identify forward-looking statements. All forward-looking statements address matters that involve risks and uncertainties. Accordingly, there are important factors that could cause actual results to differ materially from those indicated in such statements and you should not place undue reliance on any such statements.

These factors include, but are not limited to, the following: (1) the adequacy of loss reserves and the need to adjust such reserves as claims develop over time; (2) the failure of any of the loss limitation methods employed; (3) the effect of cyclical trends, including with respect to demand and pricing in the insurance and reinsurance markets; (4) changes in general economic conditions, including changes in capital and credit markets; (5) any lowering or loss of financial ratings; (6) the occurrence of natural or man-made catastrophic events with a frequency or severity exceeding expectations; (7) actions by competitors, including consolidation; (8) the effects of emerging claims and coverage issues; (9) the loss of business provided to Alterra by its major brokers; (10) the effect on Alterra’s investment portfolio of changing financial market conditions including inflation, interest rates, liquidity and other factors; (11) tax and regulatory changes and conditions; (12) retention of key personnel; and (13) the integration of new business ventures Alterra may enter into; as well as management’s response to any of the aforementioned factors.

The foregoing review of important factors should not be construed as exhaustive and should be read in conjunction with the other cautionary statements that are included herein and elsewhere, including the Risk Factors included in Alterra’s most recent reports on Form 10-K and Form 10-Q and other documents on file with the U.S. Securities and Exchange Commission. Any forward-looking statements made in this financial supplement are qualified by these cautionary statements, and there can be no assurance that the actual results or developments anticipated by Alterra will be realized or, even if substantially realized, that they will have the expected consequences to, or effects on, Alterra or its business or operations. Alterra undertakes no obligation to update publicly or revise any forward-looking statement, whether as a result of new information, future developments or otherwise.

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ALTERRA CAPITAL HOLDINGS LIMITED

FINANCIAL SUPPLEMENT TABLE OF CONTENTS

	Page
Financial Highlights		4
Consolidated Balance Sheets		5
Consolidated Statements of Income - Quarterly		6
Segment Data and Ratios - Quarterly		8
Gross Premiums Written by Line of Business - Quarterly		15
Investment Portfolio		17
Shareholder Return Analysis		20
Earnings Per Share Information		21
Operating Income Reconciliation		22
Book Value per Share		23
Regulation G		24
Reclassified Historical Segment Information		25
Pro forma Consolidated Statements of Income		29

ALTERRA CAPITAL HOLDINGS LIMITED

FINANCIAL HIGHLIGHTS

(Expressed in thousands of United States Dollars, except per share and share amounts)

	For The Quarters Ended
	March 31, 2011			March 31, 2010			Previous Year Quarter Change
HIGHLIGHTS
Net (loss) income	$	(46,687	)	$	36,381			(228.3	%)
Net operating (loss) income [a]		(24,725	)		40,681			(160.8	%)
Operating cashflow		46,909			46,800			0.2	%
Gross premiums written		627,848			371,139			69.2	%
Net premiums earned		379,887			194,240			95.6	%
Total assets		10,250,379			7,474,206			37.1	%
Total shareholders’ equity		2,723,194			1,613,116			68.8	%
PER SHARE
Basic earnings per share
Net (loss) income	$	(0.44	)	$	0.64
Net operating (loss) income [a]		(0.23	)		0.72
Diluted earnings per share
Net (loss) income	$	(0.44	)	$	0.63
Net operating (loss) income [a]		(0.23	)		0.71
Weighted average shares outstanding - basic		107,165,228			56,516,593
Weighted average shares outstanding - diluted		107,165,228			57,383,748
Book value per common share [b]	$	25.76		$	28.31			(9.0	%)
Diluted book value per share (treasury stock method) [b]		25.34			27.86			(9.1	%)
Diluted tangible book value per share (treasury stock method) [b]		24.79			27.02			(8.2	%)
RATIOS
Annualized return on average shareholders’ equity [c]		(6.6	%)		9.2	%
Annualized net operating return on average shareholders’ equity [c]		(3.5	%)		10.2	%
Loss ratio [d]		80.2	%		64.6	%
Acquisition cost ratio [d]		18.6	%		12.5	%
General and administrative expense ratio [d]		13.8	%		13.5	%
Combined ratio [d]		112.5	%		90.5	%

[a] Net operating income represents net income excluding, as applicable, after-tax net realized and unrealized gains and losses on non-hedge fund investments, after-tax net foreign exchange gains or losses, and after-tax merger and acquisition expenses.

[b] For detailed calculations see page 23.

[c] For detailed calculations see page 20.

[d] For property and casualty business only.

4

ALTERRA CAPITAL HOLDINGS LIMITED

CONSOLIDATED BALANCE SHEETS

(Expressed in thousands of United States Dollars, except per share and share amounts)

	Mar. 31, 2011			Dec. 31, 2010			Sept. 30, 2010			June 30, 2010			Mar. 31, 2010
	(Unaudited)						(Unaudited)			(Unaudited)			(Unaudited)
ASSETS
Cash and cash equivalents	$	1,001,051		$	905,606		$	925,752		$	741,684		$	690,246
Fixed maturities, trading, at fair value		214,807			244,872			243,158			230,251			219,332
Fixed maturities, available for sale, at fair value		5,290,684			5,392,643			5,425,955			5,451,969			3,158,131
Fixed maturities, held to maturity, at amortized cost		983,207			940,104			954,623			871,651			954,696
Other investments, at fair value		357,655			378,128			411,275			436,757			325,359
Accrued interest income		69,497			75,414			73,622			67,561			51,906
Premiums receivable		809,483			588,537			664,603			780,025			617,560
Losses and benefits recoverable from reinsurers		1,053,223			956,115			976,819			962,442			1,023,224
Deferred acquisition costs		149,197			111,901			106,728			89,881			72,195
Prepaid reinsurance premiums		176,918			149,252			173,140			207,102			232,947
Trades pending settlement		—			32,393			24,364			—			—
Goodwill and intangible assets		58,585			59,076			60,670			60,670			48,686
Other assets		86,072			83,247			78,225			74,943			79,924
Total assets	$	10,250,379		$	9,917,288		$	10,118,934		$	9,974,936		$	7,474,206
LIABILITIES
Property and casualty losses	$	4,185,230		$	3,906,134		$	3,847,366		$	3,772,622		$	3,220,357
Life and annuity benefits		1,316,287			1,275,580			1,299,190			1,209,031			1,306,916
Deposit liabilities		147,424			147,612			147,212			147,727			149,028
Funds withheld from reinsurers		122,072			121,107			119,859			120,324			138,984
Unearned property and casualty premiums		1,065,160			905,487			1,015,831			1,090,323			690,013
Reinsurance balances payable		127,299			102,942			122,184			295,979			168,329
Accounts payable and accrued expenses		103,376			99,680			90,282			81,846			61,955
Trades pending settlement		19,855			—			—			39,641			35,033
Bank loans		—			—			—			200,000			—
Senior notes		440,482			440,476			440,473			90,476			90,475
Total liabilities		7,527,185			6,999,018			7,082,397			7,047,969			5,861,090
SHAREHOLDERS’ EQUITY
Preferred shares (par value $1.00) 20,000,000 shares authorized; no shares issued or outstanding		—			—			—			—			—
Common shares (par value $1.00) 200,000,000 shares authorized; 105,733,610 shares issued and outstanding		105,734			110,963			115,899			118,643			56,980
Additional paid-in capital		1,905,144			2,026,045			2,113,732			2,157,700			744,466
Accumulated other comprehensive income		89,233			98,946			190,325			102,718			49,822
Retained earnings		623,083			682,316			616,581			547,906			761,848
Total shareholders’ equity		2,723,194			2,918,270			3,036,537			2,926,967			1,613,116
Total liabilities and shareholders’ equity	$	10,250,379		$	9,917,288		$	10,118,934		$	9,974,936		$	7,474,206
Book value per share	$	25.76		$	26.30		$	26.20		$	24.67		$	28.31
Diluted book value per share (treasury stock method)	$	25.34		$	25.99		$	25.88		$	24.55		$	27.86
Diluted tangible book value per share (treasury stock method)	$	24.79		$	25.46		$	25.37		$	24.04		$	27.02
Debt-to-capital ratio [a]		13.9	%		13.1	%		12.7	%		9.0	%		5.3	%

[a] Calculated as debt, being bank loans and senior notes, divided by shareholders’ equity plus debt.

5

ALTERRA CAPITAL HOLDINGS LIMITED

CONSOLIDATED STATEMENTS OF INCOME AND COMPREHENSIVE INCOME - QUARTERLY (Unaudited)

(Expressed in thousands of United States Dollars, except per share and share amounts)

	FOR THE QUARTERS ENDED
	Mar. 31, 2011			Dec. 31, 2010			Sept. 30, 2010			June 30, 2010 [f]			Mar. 31, 2010			Mar. 31, 2009
REVENUES
Gross premiums written	$	627,848		$	315,398		$	325,213		$	398,981		$	371,139		$	434,273
Reinsurance premiums ceded		(137,357	)		(77,617	)		(60,611	)		(79,715	)		(153,220	)		(164,379	)
Net premiums written	$	490,491		$	237,781		$	264,602		$	319,266		$	217,919		$	269,894
Earned premiums	$	489,262		$	445,683		$	436,244		$	391,723		$	304,997		$	309,382
Earned premiums ceded		(109,375	)		(103,129	)		(93,812	)		(98,463	)		(110,757	)		(119,100	)
Net premiums earned		379,887			342,554			342,432			293,260			194,240			190,282
Net investment income		57,766			61,080			59,711			53,277			48,390			40,488
Net realized and unrealized (losses) gains on investments		(18,818	)		9,825			15,411			(14,786	)		6,422			18,441
Total other-than-temporary impairment losses		(1,124	)		(3,918	)		(90	)		(1,167	)		(698	)		—
Portion of loss recognized in other comprehensive income (loss) before taxes		95			2,144			(61	)		867			278			—
Net impairment losses recognized in earnings		(1,029	)		(1,774	)		(151	)		(300	)		(420	)		—
Other income		1,315			2,862			1,327			275			344			1,306
Total revenues		419,121			414,547			418,730			331,726			248,976			250,517
LOSSES AND EXPENSES
Net losses and loss expenses		304,406			179,047			191,012			159,817			124,965			124,723
Claims and policy benefits		14,710			18,551			15,060			13,943			17,659			14,332
Acquisition costs		70,608			53,563			60,859			48,798			24,244			20,630
Interest expense		8,459			7,866			7,551			7,916			4,942			3,939
Net foreign exchange (gains) losses		(878	)		(382	)		3,353			(634	)		(2,452	)		(3,476	)
Merger and acquisition expenses		—			500			550			(54,570	)		4,744			5,223
General and administrative expenses		71,203			76,759			56,650			50,649			36,528			39,060
Total losses and expenses		468,508			335,904			335,035			225,919			210,630			204,431
(LOSS) INCOME BEFORE TAXES		(49,387	)		78,643			83,695			105,807			38,346			46,086
Income tax (benefit) expense		(2,700	)		(1,027	)		858			2,360			1,965			1,547
NET (LOSS) INCOME		(46,687	)		79,670			82,837			103,447			36,381			44,539
Change in net unrealized gains and losses on fixed maturities, net of tax		(14,586	)		(87,633	)		74,383			60,525			34,131			(66,098	)
Foreign currency translation adjustment		4,873			(3,746	)		13,224			(7,629	)		(9,740	)		3,909
COMPREHENSIVE (LOSS) INCOME	$	(56,400	)	$	(11,709	)	$	170,444		$	156,343		$	60,772		$	(17,650	)
KEY RATIOS/PER SHARE DATA
Loss ratio [a]		80.2	%		52.5	%		56.0	%		54.6	%		64.6	%		65.7	%
Acquisition cost ratio [b]		18.6	%		15.7	%		17.8	%		16.6	%		12.5	%		10.8	%
General and administrative expense ratio [c]		13.8	%		16.6	%		12.2	%		12.1	%		13.4	%		13.2	%
Combined ratio		112.5	%		84.8	%		86.0	%		83.3	%		90.5	%		89.7	%
Basic earnings per share	$	(0.44	)	$	0.71		$	0.71		$	1.14		$	0.64		$	0.79
Diluted earnings per share	$	(0.44	)	$	0.70		$	0.70		$	1.13		$	0.63		$	0.78
Net operating (loss) income per share - diluted [d]	$	(0.23	)	$	0.64		$	0.64		$	0.64		$	0.71		$	0.82
Annualized ROAE [e]		(6.6	%)		11.1	%		11.1	%		17.8	%		9.2	%		14.0	%
Annualized net operating ROAE [e]		(3.5	%)		10.2	%		10.2	%		10.1	%		10.2	%		14.8	%

[a] The loss ratio is calculated by dividing net losses and loss expenses by net premiums earned for the property & casualty business

[b] The acquisition cost ratio is calculated by dividing acquisition costs by net premiums earned for the property & casualty business

[c] The general and administrative expense ratio is calculated by dividing general and administrative expenses by net premiums earned for the property & casualty business

[d] See page 22 for calculation of net operating income per share - diluted.

[e] See page 20 for calculation of annualized return on average shareholders’ equity (ROAE) and annualized net operating ROAE

[f] Includes the results for Harbor Point Limited (“Harbor Point”) from May 12, 2010.

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ALTERRA CAPITAL HOLDINGS LIMITED

SCHEDULE OF SUPPLEMENTAL UNDERWRITING DATA–THREE MONTHS ENDED MARCH 31, 2011 (Unaudited)

(Expressed in thousands of United States Dollars)

	Property & Casualty															Life & Annuity			Corporate			Consolidated
	Insurance			Reinsurance			U.S. Specialty			Alterra at Lloyd’s			Total			Reinsurance
Gross premiums written	$	71,272		$	375,020		$	70,388		$	110,733		$	627,413		$	435		$	—		$	627,848
Reinsurance premiums ceded		(43,246	)		(37,317	)		(33,595	)		(23,179	)		(137,337	)		(20	)		—			(137,357	)
Net premiums written	$	28,026		$	337,703		$	36,793		$	87,554		$	490,076		$	415		$	—		$	490,491
Earned premiums	$	98,944		$	249,901		$	73,177		$	66,805		$	488,827		$	435		$	—		$	489,262
Earned premiums ceded		(44,730	)		(20,195	)		(23,850	)		(20,580	)		(109,355	)		(20	)		—			(109,375	)
Net premiums earned		54,214			229,706			49,327			46,225			379,472			415			—			379,887
Net losses and loss expenses		(34,664	)		(186,885	)		(31,375	)		(51,482	)		(304,406	)		—			—			(304,406	)
Claims and policy benefits		—			—			—			—			—			(14,710	)		—			(14,710	)
Acquisition costs		(184	)		(49,143	)		(8,066	)		(13,056	)		(70,449	)		(159	)		—			(70,608	)
General and administrative expenses		(9,825	)		(23,258	)		(9,397	)		(9,723	)		(52,203	)		(177	)		—			(52,380	)
Other income		812			—			—			215			1,027			—			—			1,027
Underwriting income (loss)		10,353			(29,580	)		489			(27,821	)		(46,559	)		n/a			—			n/a
Net investment income																	12,343			45,423			57,766
Net realized and unrealized gains (losses) on investments																	2,807			(21,625	)		(18,818	)
Net impairment losses recognized in earnings																				(1,029	)		(1,029	)
Corporate other income																				288			288
Interest expense																				(8,459	)		(8,459	)
Net foreign exchange gains																				878			878
Corporate general and administrative expenses																				(18,823	)		(18,823	)
Income (loss) before taxes																$	519		$	(3,347	)	$	(49,387	)
Loss ratio [a]		63.9	%		81.4	%		63.6	%		111.4	%		80.2	%
Acquisition cost ratio [b]		0.3	%		21.4	%		16.4	%		28.2	%		18.6	%
General and administrative expense ratio [c]		18.1	%		10.1	%		19.1	%		21.0	%		13.8	%
Combined ratio		82.4	%		112.9	%		99.0	%		160.7	%		112.5	%

[a] The loss ratio is calculated by dividing net losses and loss expenses by net premiums earned for the property & casualty business

[b] The acquisition cost ratio is calculated by dividing acquisition costs by net premiums earned for the property & casualty business

[c] The general and administrative expense ratio is calculated by dividing general and administrative expenses by net premiums earned for the property & casualty business

Percentage totals may not add due to rounding.

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ALTERRA CAPITAL HOLDINGS LIMITED

CONSOLIDATED UNDERWRITING RATIOS - THREE MONTHS ENDED MARCH 31, 2011 (Unaudited)

	Property & Casualty
	Insurance			Reinsurance			U.S. Specialty			Alterra at Lloyd’s			Total
UNDERWRITING RATIOS
Loss ratio		63.9	%		81.4	%		63.6	%		111.4	%		80.2	%
Acquisition cost ratio		0.3	%		21.4	%		16.4	%		28.2	%		18.6	%
General and administrative expense ratio		18.1	%		10.1	%		19.1	%		21.0	%		13.8	%
Combined ratio		82.4	%		112.9	%		99.0	%		160.7	%		112.5	%
EFFECT OF PRIOR ACCIDENT YEAR RESERVE DEVELOPMENT FAVORABLE / (UNFAVORABLE)
Loss ratio [a]		13.5	%		9.9	%		0.0	%		0.0	%		8.0	%
NET OF PRIOR ACCIDENT YEAR RESERVE DEVELOPMENT UNDERWRITING RATIOS
Loss ratio		77.4	%		91.3	%		63.6	%		111.4	%		88.2	%
Acquisition cost ratio		0.3	%		21.4	%		16.4	%		28.2	%		18.6	%
General and administrative expense ratio		18.1	%		10.1	%		19.1	%		21.0	%		13.8	%
Combined ratio		95.9	%		122.8	%		99.0	%		160.7	%		120.5	%

[a] Prior accident year reserve development excludes changes in reserves resulting from changes in premium estimates on prior years’ contracts.

CONSOLIDATED UNDERWRITING RATIOS - THREE MONTHS ENDED MARCH 31, 2010 (Unaudited)

	Property & Casualty
	Insurance [c]			Reinsurance			U.S. Specialty [c]			Alterra at Lloyd’s			Total			Historical Harbor Point [b]
UNDERWRITING RATIOS
Loss ratio		74.5	%		62.7	%		62.3	%		54.2	%		64.6	%		63.7	%
Acquisition cost ratio		(0.6	%)		18.8	%		12.0	%		19.2	%		12.5	%		20.6	%
General and administrative expense ratio		12.9	%		11.2	%		24.4	%		9.0	%		13.5	%		5.9	%
Combined ratio		86.9	%		92.7	%		98.7	%		82.5	%		90.5	%		90.2	%
EFFECT OF PRIOR ACCIDENT YEAR RESERVE DEVELOPMENT FAVORABLE / (UNFAVORABLE)
Loss ratio [a]		11.0	%		11.6	%		2.2	%		5.5	%		8.8	%		5.2	%
NET OF PRIOR ACCIDENT YEAR RESERVE DEVELOPMENT UNDERWRITING RATIOS
Loss ratio		85.5	%		74.3	%		64.5	%		59.7	%		73.4	%		68.9	%
Acquisition cost ratio		(0.6	%)		18.8	%		12.0	%		19.2	%		12.5	%		20.6	%
General and administrative expense ratio		12.9	%		11.2	%		24.4	%		9.0	%		13.5	%		5.9	%
Combined ratio		97.9	%		104.3	%		100.9	%		88.0	%		99.3	%		95.4	%

[a] Prior accident year reserve development excludes changes in reserves resulting from changes in premium estimates on prior years’ contracts.

[b] Provided for informational purposes only.

[c] Insurance and U.S. Specialty segment amounts for the comparative 2010 period have been reclassified to conform with the current period’s presentation.

Percentage totals may not add due to rounding.

8

ALTERRA CAPITAL HOLDINGS LIMITED

INSURANCE SEGMENT DATA (Unaudited)

(Expressed in thousands of United States Dollars)

	FOR THE QUARTERS ENDED
	Mar. 31, 2011			Dec. 31, 2010 [a]			Sept. 30, 2010 [a]			June 30, 2010 [a]			Mar. 31, 2010 [a]			Mar. 31, 2009 [a]
Gross premiums written	$	71,272		$	113,236		$	77,944		$	139,026		$	69,406		$	91,006
Reinsurance premiums ceded		(43,246	)		(56,728	)		(36,875	)		(47,437	)		(39,651	)		(56,220	)
Net premiums written	$	28,026		$	56,508		$	41,069		$	91,589		$	29,755		$	34,786
Earned premiums	$	98,944		$	106,169		$	102,640		$	104,841		$	101,746		$	105,640
Earned premiums ceded		(44,730	)		(43,847	)		(42,796	)		(45,211	)		(48,830	)		(53,178	)
Net premiums earned		54,214			62,322			59,844			59,630			52,916			52,462
Net losses and loss expenses		(34,664	)		(35,687	)		(26,679	)		(38,296	)		(39,446	)		(38,158	)
Acquisition costs		(184	)		(1,765	)		(1,382	)		(821	)		317			1,367
General and administrative expenses		(9,825	)		(11,812	)		(7,717	)		(8,132	)		(6,847	)		(6,074	)
Other income		812			68			1,108			97			(6	)		1,216
Underwriting income	$	10,353		$	13,126		$	25,174		$	12,478		$	6,934		$	10,813
Loss ratio		63.9	%		57.3	%		44.6	%		64.2	%		74.5	%		72.7	%
Acquisition cost ratio		0.3	%		2.8	%		2.3	%		1.4	%		(0.6	%)		(2.6	%)
General and administrative expense ratio		18.1	%		18.9	%		12.9	%		13.6	%		12.9	%		11.6	%
Combined ratio		82.4	%		79.0	%		59.8	%		79.2	%		86.9	%		81.7	%

[a] Insurance and U.S. Specialty segment amounts for comparative periods have been reclassified to conform with the current period’s presentation.

See page 25 for additional information.

9

ALTERRA CAPITAL HOLDINGS LIMITED

REINSURANCE SEGMENT DATA (Unaudited)

(Expressed in thousands of United States Dollars)

	FOR THE QUARTERS ENDED
	Mar. 31, 2011			Dec. 31, 2010			Sept. 30, 2010			June 30, 2010 [a]			Mar. 31, 2010			Mar. 31, 2009
Gross premiums written	$	375,020		$	110,620		$	124,004		$	119,578		$	154,851		$	232,982
Reinsurance premiums ceded		(37,317	)		(2,908	)		(2,524	)		(13,348	)		(45,351	)		(51,383	)
Net premiums written	$	337,703		$	107,712		$	121,480		$	106,230		$	109,500		$	181,599
Earned premiums	$	249,901		$	215,261		$	213,510		$	174,729		$	95,743		$	123,986
Earned premiums ceded		(20,195	)		(21,082	)		(15,533	)		(19,054	)		(15,958	)		(26,519	)
Net premiums earned		229,706			194,179			197,977			155,675			79,785			97,467
Net losses and loss expenses		(186,885	)		(97,639	)		(117,671	)		(82,441	)		(50,065	)		(66,215	)
Acquisition costs		(49,143	)		(38,406	)		(45,069	)		(32,673	)		(14,966	)		(17,463	)
General and administrative expenses		(23,258	)		(24,714	)		(17,580	)		(14,820	)		(8,959	)		(7,524	)
Other income		—			(216	)		61			155			—			—
Underwriting income (loss)	$	(29,580	)	$	33,204		$	17,718		$	25,896		$	5,795		$	6,265
Loss ratio		81.4	%		50.3	%		59.4	%		53.0	%		62.7	%		67.9	%
Acquisition cost ratio		21.4	%		19.8	%		22.8	%		21.0	%		18.8	%		18.0	%
General and administrative expense ratio		10.1	%		12.7	%		8.9	%		9.5	%		11.2	%		7.7	%
Combined ratio		112.9	%		82.8	%		91.1	%		83.5	%		92.7	%		93.6	%

[a] Includes the results for Harbor Point from May 12, 2010.

10

ALTERRA CAPITAL HOLDINGS LIMITED

PRO FORMA ALTERRA REINSURANCE SEGMENT SELECTED FINANCIAL INFORMATION [a] (Unaudited)

(Expressed in thousands of United States Dollars)

	FOR THE QUARTERS ENDED
	Dec. 31, 2010			Sept. 30, 2010			June 30, 2010			Mar. 31, 2010			Dec. 31, 2009			Sept. 30, 2009			June 30, 2009			Mar. 31, 2009
Gross premiums written	$	110,620		$	124,004		$	197,146		$	460,618		$	125,447		$	210,882		$	262,938		$	461,141
Net premiums earned		194,179			197,977			226,291			215,050			230,516			238,953			221,120			220,103
Net losses and loss expenses		97,639			117,671			136,158			129,727			108,941			113,625			118,613			115,706
Acquisition costs		38,406			45,069			47,179			42,689			46,708			50,167			42,586			43,280
General and administrative expenses		24,714			17,580			16,527			16,824			23,680			19,726			18,520			19,201
Loss ratio		50.3	%		59.4	%		60.2	%		60.3	%		47.3	%		47.6	%		53.6	%		52.6	%
Acquisition cost ratio		19.8	%		22.8	%		20.8	%		19.9	%		20.3	%		21.0	%		19.3	%		19.7	%
General and administrative expense ratio		12.7	%		8.9	%		7.3	%		7.8	%		10.2	%		8.2	%		8.4	%		8.7	%
Combined ratio		82.8	%		91.1	%		88.3	%		88.0	%		77.8	%		76.8	%		81.3	%		81.0	%

[a] This information is based on historical Alterra reinsurance segment financial information adjusted to include Harbor Point historical financial information as though the amalgamation with Harbor Point had occurred on January 1, 2009. The financial information also includes adjustments to eliminate any intercompany transactions and to reflect the amortization of certain acquisition accounting fair value adjustments.

The pro forma information is provided for informational purposes only. The pro forma information does not necessarily represent results that would have occurred if the amalgamation had occurred on January 1, 2009, nor is it necessarily indicative of future results.

11

ALTERRA CAPITAL HOLDINGS LIMITED

U.S. SPECIALTY SEGMENT DATA (Unaudited)

(Expressed in thousands of United States Dollars)

	FOR THE QUARTERS ENDED
	Mar. 31, 2011			Dec. 31, 2010 [a]			Sept. 30, 2010 [a]			June 30, 2010 [a]			Mar. 31, 2010 [a]			Mar. 31, 2009 [a]
Gross premiums written	$	70,388		$	65,625		$	64,198		$	90,773		$	73,902		$	65,509
Reinsurance premiums ceded		(33,595	)		(15,956	)		(18,713	)		(5,672	)		(48,152	)		(39,382	)
Net premiums written	$	36,793		$	49,669		$	45,485		$	85,101		$	25,750		$	26,127
Earned premiums	$	73,177		$	74,683		$	73,337		$	71,065		$	69,185		$	50,913
Earned premiums ceded		(23,850	)		(26,140	)		(26,071	)		(27,053	)		(38,393	)		(31,926	)
Net premiums earned		49,327			48,543			47,266			44,012			30,792			18,987
Net losses and loss expenses		(31,375	)		(31,878	)		(29,295	)		(26,683	)		(19,196	)		(10,391	)
Acquisition costs		(8,066	)		(8,618	)		(6,763	)		(9,111	)		(3,682	)		(1,189	)
General and administrative expenses		(9,397	)		(7,552	)		(8,693	)		(6,355	)		(7,522	)		(6,811	)
Other income		—			—			—			—			—			(221	)
Underwriting income	$	489		$	495		$	2,515		$	1,863		$	392		$	375
Loss ratio		63.6	%		65.7	%		62.0	%		60.6	%		62.3	%		54.7	%
Acquisition cost ratio		16.4	%		17.8	%		14.3	%		20.7	%		12.0	%		6.3	%
General and administrative expense ratio		19.1	%		15.5	%		18.4	%		14.5	%		24.4	%		35.9	%
Combined ratio		99.0	%		99.0	%		94.7	%		95.8	%		98.7	%		96.9	%

[a] Insurance and U.S. Specialty segment amounts for comparative periods have been reclassified to conform with the current period’s presentation. See page 25 for additional information.

12

ALTERRA CAPITAL HOLDINGS LIMITED

ALTERRA AT LLOYD’S SEGMENT DATA (Unaudited)

(Expressed in thousands of United States Dollars)

	FOR THE QUARTERS ENDED
	Mar. 31, 2011			Dec. 31, 2010			Sept. 30, 2010			June 30, 2010			Mar. 31, 2010			Mar. 31, 2009
Gross premiums written	$	110,733		$	23,980		$	57,734		$	48,802		$	72,117		$	44,179
Reinsurance premiums ceded		(23,179	)		(1,859	)		(2,397	)		(13,233	)		(19,959	)		(17,301	)
Net premiums written	$	87,554		$	22,121		$	55,337		$	35,569		$	52,158		$	26,878
Earned premiums	$	66,805		$	47,633		$	45,424		$	40,286		$	37,460		$	28,246
Earned premiums ceded		(20,580	)		(11,894	)		(9,310	)		(7,120	)		(7,469	)		(7,384	)
Net premiums earned		46,225			35,739			36,114			33,166			29,991			20,862
Net losses and loss expenses		(51,482	)		(13,843	)		(17,367	)		(12,397	)		(16,258	)		(9,959	)
Acquisition costs		(13,056	)		(4,853	)		(7,474	)		(6,070	)		(5,767	)		(3,152	)
General and administrative expenses		(9,723	)		(12,186	)		(7,806	)		(5,826	)		(2,713	)		(4,721	)
Other income		215			2,006			177			173			178			72
Underwriting (loss) income	$	(27,821	)	$	6,863		$	3,644		$	9,046		$	5,431		$	3,102
Loss ratio		111.4	%		38.7	%		48.1	%		37.4	%		54.2	%		47.7	%
Acquisition cost ratio		28.2	%		13.6	%		20.7	%		18.3	%		19.2	%		15.1	%
General and administrative expense ratio		21.0	%		34.1	%		21.6	%		17.5	%		9.0	%		22.7	%
Combined ratio		160.7	%		86.4	%		90.4	%		73.2	%		82.5	%		85.5	%

13

ALTERRA CAPITAL HOLDINGS LIMITED

LIFE AND ANNUITY REINSURANCE SEGMENT DATA (Unaudited)

(Expressed in thousands of United States Dollars)

	FOR THE QUARTERS ENDED
	Mar. 31, 2011			Dec. 31, 2010			Sept. 30, 2010			June 30, 2010			Mar. 31, 2010			Mar. 31, 2009
Gross premiums written	$	435		$	1,937		$	1,333		$	802		$	863		$	597
Reinsurance premiums ceded		(20	)		(166	)		(102	)		(25	)		(107	)		(93	)
Net premiums written	$	415		$	1,771		$	1,231		$	777		$	756		$	504
Earned premiums	$	435		$	1,937		$	1,333		$	802		$	863		$	597
Earned premiums ceded		(20	)		(166	)		(102	)		(25	)		(107	)		(93	)
Net premiums earned		415			1,771			1,231			777			756			504
Net investment income		12,343			12,084			12,182			12,420			13,099			11,566
Net realized and unrealized gains (losses) on investments		2,807			3,981			3,321			(1,860	)		5,916			7,868
Other income		—			357			(43	)		—			(28	)		—
Claims and policy benefits		(14,710	)		(18,551	)		(15,060	)		(13,943	)		(17,659	)		(14,332	)
Acquisition costs		(159	)		79			(171	)		(123	)		(146	)		(193	)
General and administrative expenses		(177	)		(1,088	)		(577	)		(642	)		(657	)		(695	)
Income (loss) before taxes	$	519		$	(1,367	)	$	883		$	(3,371	)	$	1,281		$	4,718

14

ALTERRA CAPITAL HOLDINGS LIMITED

SEGMENT GROSS PREMIUMS WRITTEN BY LINE OF BUSINESS (Unaudited)

(Expressed in thousands of United States Dollars)

		FOR THE QUARTERS ENDED
		Mar. 31, 2011			Dec. 31, 2010			Sept. 30, 2010			June 30, 2010			Mar. 31, 2010		Mar. 31, 2009
Gross Premiums Written by Type of Risk:
Property & Casualty:
Insurance [a]:
Aviation	S	$	1,416		$	22,677		$	8,247		$	6,615		$	2,349	$	6,185
Excess Liability	L		27,387			27,361			21,579			38,001			26,633		37,972
Professional Liability	L		26,796			51,199			37,151			67,127			27,573		32,441
Property	S		15,673			11,999			10,967			27,283			12,851		14,408
			71,272			113,236			77,944			139,026			69,406		91,006
Reinsurance [b]:
Agriculture	S	$	20,785		$	(1,406	)		(2,665	)		(2,513	)		35,806		87,666
Auto	S		15,160			22,585			10,251			66			—		—
Aviation	S		904			2,596			15,313			8,561			4,822		4,159
Credit/ Surety	S		24,426			1,118			2,569			(1,491	)		—		—
General Casualty	L		16,247			17,658			18,505			(857	)		13,051		18,141
Marine & Energy	S		17,093			(1,549	)		8,826			5,004			4,100		9,078
Medical Malpractice	L		17,582			19,554			(3,131	)		7,813			27,155		36,393
Other	S		1,759			520			1,183			92			989		1,866
Professional Liability	L		59,684			28,538			37,965			32,005			11,919		9,711
Property	S		149,874			6,296			34,859			61,058			45,933		42,181
Whole Account	S/L		35,070			426			(232	)		2,362			2,573		4,375
Workers’ Compensation	L		16,436			14,284			561			7,478			8,503		19,412
			375,020			110,620			124,004			119,578			154,851		232,982
U.S. Specialty [a]:
General Liability	L	$	17,883		$	19,914			18,371			22,822			20,029		15,619
Marine	S		17,109			17,758			15,637			17,996			16,063		14,781
Professional Liability	L		4,355			(534	)		3,135			1,756			2,246		—
Property	S		31,041			28,487			27,055			48,199			35,564		35,109
			70,388			65,625			64,198			90,773			73,902		65,509
Alterra at Lloyd’s:
Accident & Health	S		13,544		$	5,570			5,919			6,022			13,410		12,410
Aviation	S		1,767			5,224			3,946			2,565			4,403		—
Financial Institutions	L		9,036			384			8,130			4,846			6,088		3,824
International Casualty	L		33,860			2,213			4,095			6,182			13,684		—
Professional Liability	L		7,922			4,204			4,330			4,161			6,896		2,785
Property	S		44,623			5,946			26,945			25,026			27,636		25,160
Surety	S		(19	)		439			4,369			—			—		—
			110,733			23,980			57,734			48,802			72,117		44,179
Aggregate Property & Casualty		$	627,413		$	313,461		$	323,880		$	398,179		$	370,276	$	433,676
Life & Annuity:
Annuity		$	336		$	1,129		$	—		$	6		$	—	$	—
Life			99			808			1,333			796			863		597
Aggregate Life & Annuity			435			1,937			1,333			802			863		597
Aggregate Property & Casualty and Life & Annuity		$	627,848		$	315,398		$	325,213		$	398,981		$	371,139	$	434,273

[a] Insurance and U.S. specialty segment amounts for comparative periods have been reclassified to conform with the current period’s presentation.

[b] Includes the results for Harbor Point from May 12, 2010.

S = Short tail lines	$	372,690	$	128,473	$	173,305	$	205,664	$	205,213	$	255,191
L = Long tail lines		254,723		184,988		150,575		192,515		165,063		178,486
Aggregate Property & Casualty	$	627,413	$	313,461	$	323,880	$	398,179	$	370,276	$	433,676

15

ALTERRA CAPITAL HOLDINGS LIMITED

PRO FORMA ALTERRA REINSURANCE SEGMENT GROSS PREMIUMS WRITTEN BY LINE OF BUSINESS [a] (Unaudited)

(Expressed in thousands of United States Dollars)

		FOR THE QUARTERS ENDED
		Dec. 31, 2010			Sept. 30, 2010			June 30, 2010			Mar. 31, 2010		Dec. 31, 2009		Sept. 30, 2009			June 30, 2009			Mar. 31, 2009
Gross Premiums Written by Type of Risk:
Agriculture	S	$	(1,406	)	$	(2,665	)	$	(4,643	)	$	55,944	$	2,153	$	(96	)	$	(262	)	$	91,196
Auto	S		22,585			10,251			14,359			18,063		19,531		12,828			11,288			15,148
Aviation	S		2,596			15,313			8,586			6,191		9,395		18,154			10,760			4,509
Credit/ Surety	S		1,118			2,569			1,530			23,555		9,058		369			2,440			8,828
General Casualty	L		17,658			18,505			6,724			42,398		15,607		31,167			10,225			36,892
Marine & Energy	S		(1,549	)		8,826			5,220			21,128		4,033		8,565			(3,731	)		37,799
Medical Malpractice	L		19,554			(3,131	)		6,424			33,804		11,093		7,077			21,783			36,417
Other	S		520			1,183			294			5,664		168		(57	)		485			3,011
Professional Liability	L		28,538			37,965			51,615			55,812		37,407		60,373			53,705			50,629
Property	S		6,296			34,859			96,745			138,958		2,260		34,240			118,581			142,118
Whole Account	S/L		426			(232	)		3,095			47,135		6,578		4,569			18,503			5,369
Workers’ Compensation	L		14,284			561			7,197			11,966		8,164		33,693			19,161			29,225
Aggregate Pro Forma Reinsurance Segment		$	110,620		$	124,004		$	197,146		$	460,618	$	125,447	$	210,882		$	262,938		$	461,141

[a] This information is based on historical Alterra reinsurance segment gross premiums written adjusted to include Harbor Point historical gross premiums written as though the amalgamation with Harbor Point had occurred on January 1, 2009. The financial information also includes adjustments to eliminate any intercompany transactions.

The pro forma information is provided for informational purposes only. The pro forma information does not necessarily represent results that would have occurred if the amalgamation with Harbor Point had occurred on January 1, 2009, nor is it necessarily indicative of future results.

16

ALTERRA CAPITAL HOLDINGS LIMITED

INVESTMENT PORTFOLIO (Unaudited)

(Expressed in thousands of United States Dollars)

	Carrying Value										Fair Value
Type of Investment	As of Mar. 31, 2011		Investment Distribution			As of Dec. 31, 2010		Investment Distribution			As of Mar. 31, 2011		Investment Distribution			As of Dec. 31, 2010		Investment Distribution
Cash and cash equivalents	$	1,001,051		12.8	%	$	905,606		11.5	%	$	1,001,051		12.7	%	$	905,606		11.4	%
U.S. government and agencies		829,036		10.6	%		995,546		12.7	%		829,036		10.5	%		995,546		12.5	%
Non-U.S. governments		176,497		2.2	%		79,111		1.0	%		176,497		2.2	%		79,111		1.0	%
Corporate securities		2,654,351		33.8	%		2,735,366		34.8	%		2,654,351		33.6	%		2,735,366		34.5	%
Municipal securities		196,027		2.5	%		238,014		3.0	%		196,027		2.5	%		238,014		3.0	%
Asset-backed securities		114,729		1.5	%		86,937		1.1	%		114,729		1.5	%		86,937		1.1	%
Residential mortgage-backed securities		1,178,989		15.0	%		1,168,390		14.9	%		1,178,989		14.9	%		1,168,390		14.7	%
Commercial mortgage-backed securities		355,862		4.5	%		334,151		4.3	%		355,862		4.5	%		334,151		4.2	%
Fixed maturities carried at fair value	$	5,505,491		70.2	%	$	5,637,515		71.7	%	$	5,505,491		69.8	%	$	5,637,515		71.0	%
Other investments carried at fair value	$	357,655		4.6	%	$	378,128		4.8	%	$	357,655		4.5	%	$	378,128		4.8	%
Total investments carried at fair value	$	6,864,197		87.5	%	$	6,921,249		88.0	%	$	6,864,197		87.0	%	$	6,921,249		87.2	%
U.S. government and agencies	$	29,690		0.4	%	$	29,687		0.4	%	$	29,960		0.4	%	$	30,200		0.4	%
Non-U.S. governments		570,559		7.3	%		538,274		6.8	%		594,395		7.5	%		587,053		7.4	%
Corporate securities		381,958		4.9	%		371,143		4.7	%		400,949		5.1	%		397,261		5.0	%
Asset-backed securities		1,000		0.0	%		1,000		0.0	%		998		0.0	%		998		0.0	%
Fixed maturities carried at amortized cost	$	983,207		12.5	%	$	940,104		12.0	%	$	1,026,302		13.0	%	$	1,015,512		12.8	%
Total invested assets	$	7,847,404		100.0	%	$	7,861,353		100.0	%	$	7,890,499		100.0	%	$	7,936,761		100.0	%

As of March 31, 2011, the weighted average book yield of the cash and fixed maturities portfolio was 3.38%, and the weighted average duration was 4.1 years.

Credit Ratings	As of Mar. 31, 2011		Ratings Distribution			As of Dec. 31, 2010		Ratings Distribution			As of Mar. 31, 2011		Ratings Distribution			As of Dec. 31, 2010		Ratings Distribution
U.S. government and agencies [a]	$	1,914,424		29.5	%	$	2,060,116		31.3	%	$	1,914,424		29.3	%	$	2,060,116		31.0	%
AAA		1,111,873		17.1	%		1,076,680		16.4	%		1,111,873		17.0	%		1,076,680		16.2	%
AA		652,294		10.1	%		657,867		10.0	%		652,294		10.0	%		657,867		9.9	%
A		1,323,594		20.4	%		1,353,945		20.6	%		1,323,594		20.3	%		1,353,945		20.4	%
BBB		248,544		3.8	%		226,849		3.4	%		248,544		3.8	%		226,849		3.4	%
BB		31,979		0.5	%		32,021		0.5	%		31,979		0.5	%		32,021		0.5	%
B		120,738		1.9	%		138,703		2.1	%		120,738		1.8	%		138,703		2.1	%
CCC or lower		49,785		0.8	%		45,469		0.7	%		49,785		0.8	%		45,469		0.7	%
Not rated		52,260		0.8	%		45,865		0.7	%		52,260		0.8	%		45,865		0.7	%
Fixed maturities carried at fair value	$	5,505,491		84.8	%	$	5,637,515		85.7	%	$	5,505,491		84.3	%	$	5,637,515		84.7	%
U.S. government and agencies		29,690		0.5	%		29,687		0.5	%		29,960		0.5	%		30,200		0.5	%
AAA		682,948		10.5	%		641,437		9.8	%		712,759		10.9	%		699,598		10.5	%
AA		117,084		1.8	%		113,140		1.7	%		120,298		1.8	%		118,276		1.8	%
A		139,118		2.1	%		141,683		2.2	%		146,744		2.2	%		151,127		2.3	%
BBB		14,367		0.2	%		12,744		0.2	%		16,541		0.3	%		14,764		0.2	%
Not rated		—		—			1,413		0.0	%		—		—			1,547		0.0	%
Fixed maturities carried at amortized cost	$	983,207		15.2	%	$	940,104		14.3	%	$	1,026,302		15.7	%	$	1,015,512		15.3	%
Total fixed maturities	$	6,488,698		100.0	%	$	6,577,619		100.0	%	$	6,531,793		100.0	%	$	6,653,027		100.0	%

[a] Included within U.S. government and agencies are agency-issued residential mortgage-backed securities with a fair value of $1,085,388 (December 31, 2010: $1,064,570)

Percentage totals may not add due to rounding.

	Quarter Ended Mar. 31, 2011			Quarter Ended Dec. 31, 2010			Quarter Ended Sept. 30, 2010			Quarter Ended June 30, 2010			Quarter Ended Mar. 31, 2010			Quarter Ended Mar. 31, 2009
Net investment income	$	57,766		$	61,080		$	59,711		$	53,277		$	48,390		$	40,488
Realized and unrealized (losses) gains on trading fixed maturities		(1,827	)		(3,893	)		883			(1,284	)		(182	)		467
Net realized gains (losses) on available for sale fixed maturities		3,369			5,816			6,395			2,425			838			(39	)
Change in fair value of hedge funds		3,167			5,465			4,820			(3,323	)		7,370			17,465
Change in fair value of non-hedge fund other investments		(23,527	)		2,437			3,313			(12,604	)		(1,604	)		548
Net realized and unrealized (losses) gains on investments	$	(18,818	)	$	9,825		$	15,411		$	(14,786	)	$	6,422		$	18,441
Net impairment losses recognized in earnings	$	(1,029	)	$	(1,774	)	$	(151	)	$	(300	)	$	(420	)	$	—

17

ALTERRA CAPITAL HOLDINGS LIMITED

INVESTMENT PORTFOLIO (Unaudited)

(Expressed in thousands of United States Dollars)

	As of Mar. 31, 2011		Periodic Rate of Return
			Last 3 Months			Year to Date			Last 12 months			Last 60 months*
Cash and fixed maturities	$	7,489,749		1.04	%		1.04	%		4.84	%		5.24	%
Convertible arbitrage	$	—		0.00	%		0.00	%		0.00	%		0.66	%
Distressed securities		34,637		0.42	%		0.42	%		3.61	%		5.87	%
Diversified arbitrage		27,092		3.53	%		3.53	%		13.45	%		(2.61	%)
Emerging markets		10,614		1.52	%		7.62	%		4.49	%		10.10	%
Event-driven arbitrage		27,585		(4.41	%)		(11.14	%)		2.24	%		7.84	%
Fixed income arbitrage		—		0.00	%		0.00	%		3.16	%		13.18	%
Fund of funds		43,842		2.32	%		2.32	%		6.84	%		1.33	%
Global macro		50,011		0.94	%		6.27	%		5.76	%		7.77	%
Long / short credit		10,219		1.81	%		1.81	%		5.17	%		5.28	%
Long / short equity		82,615		2.95	%		2.95	%		5.31	%		5.77	%
Opportunistic		1,720		(35.82	%)		(35.82	%)		(37.04	%)		(19.55	%)
Hedge funds **		288,335		0.98	%		0.98	%		3.23	%		2.53	%
Catastrophe bonds		29,349
Derivatives		6,723
Structured deposits		28,143
Equity investments		5,105
Total other investments	$	357,655
Total invested assets	$	7,847,404
Hedge Fund Investment Return Data:
HFRI Fund of Funds Composite Index [a]				0.89	%		0.89	%		5.16	%		1.62	%
Hedge Fund Performance History – 60 months ended March 31, 2011

Monthly performance	2011			2010			2009			2008			2007			2006
January		0.13	%		0.79	%		2.13	%		(1.37	%)		1.28	%
February		0.57	%		0.17	%		0.65	%		1.83	%		1.50	%
March		0.29	%		1.02	%		(0.76	%)		(2.58	%)		1.90	%
April					0.88	%		(0.84	%)		(0.13	%)		2.30	%		1.89	%
May					(0.73	%)		2.45	%		2.51	%		2.59	%		(1.74	%)
June					(0.83	%)		1.53	%		0.93	%		0.85	%		(0.66	%)
July					0.36	%		1.40	%		(4.12	%)		0.99	%		(0.71	%)
August					(0.28	%)		0.78	%		(2.14	%)		(1.62	%)		0.02	%
September					1.28	%		1.71	%		(7.31	%)		1.85	%		(2.04	%)
October					0.84	%		1.53	%		(4.85	%)		4.15	%		1.37	%
November					0.40	%		0.35	%		(1.75	%)		0.10	%		1.81	%
December					0.31	%		0.77	%		(1.92	%)		(0.13	%)		1.96	%
Quarterly performance
Q1		0.98	%		1.99	%		2.00	%		(2.15	%)		4.75	%
Q2					(0.69	%)		3.14	%		3.33	%		5.83	%		(0.54	%)
Q3					1.35	%		3.94	%		(13.03	%)		1.18	%		(2.72	%)
Q4					1.56	%		2.66	%		(8.31	%)		4.11	%		5.22	%
Period return		0.98	%		4.25	%		12.27	%		(19.38	%)		16.78	%		1.81	%

Past performance should not be considered to be a reliable indicator of future performance.

[a] As reported by HFRI as of April 29, 2011

* Annualized

** Net of all fees

18

ALTERRA CAPITAL HOLDINGS LIMITED

LARGEST 25 CORPORATE HOLDINGS (Unaudited)

(Expressed in thousands of United States Dollars)

	As of Mar. 31, 2011
Issuer	Amortized Cost		Fair Value
European Investment Bank		59,178		61,519
General Electric		60,783		61,487
Bank of America Corp		57,717		59,092
Wells Fargo & Co		53,600		54,469
JP Morgan Chase & Co		50,932		52,279
Citigroup Inc		52,270		52,223
Kreditanstalt Fuer Wiederaufbau		48,519		50,519
Morgan Stanley		40,496		42,110
Credit Suisse Group		39,776		40,153
Lloyds Banking Group plc		37,449		38,412
Pepsico Inc		35,999		37,100
Verizon Communications Inc		34,732		35,910
BP plc		34,597		35,132
Novartis AG		33,076		34,002
AT&T Inc		33,121		33,833
UBS AG		28,155		30,180
Metlife Inc		28,346		29,025
Goldman Sachs Group Inc		27,878		28,477
Pfizer Inc		26,988		25,051
Berkshire Hathaway Inc		27,467		27,959
Conoco Philips		25,619		26,715
Hypo Real Estate Holding AG		26,080		26,317
Wal-Mart Stores Inc		23,580		23,498
Barclays plc		23,803		23,323
Medtronic Inc		22,556		22,768
	$	932,716	$	951,553

19

ALTERRA CAPITAL HOLDINGS LIMITED

SHAREHOLDER RETURN ANALYSIS (Unaudited)

(Expressed in thousands of United States Dollars, except per share and share amounts)

	FOR THE QUARTERS ENDED
	Mar. 31, 2011			Mar. 31, 2010
Income and Return on Equity:
Net (loss) income	$	(46,687	)	$	36,381
Net operating (loss) income	$	(24,725	)	$	40,681
Average shareholders’ equity	$	2,820,732		$	1,588,875
Annualized return on average shareholders’ equity [a]		(6.6	%)		9.2	%
Annualized net operating return on average shareholders’ equity [a]		(3.5	%)		10.2	%
Book value and dividends per share:
Diluted book value per share	$	25.34		$	27.86
Dividends paid per share	$	0.12		$	0.10
Change in diluted book value per share		(2.5	%)		1.8	%
Dividend payout ratio [b]		0.4	%		0.4	%
Total return to shareholders [c]		(2.1	%)		2.2	%

[a] Annualized return on average shareholders’ equity is defined as annualized net income divided by the average of the quarterly average shareholders’ equity balances.

Annualized net operating return on average shareholders’ equity is defined as annualized net operating income divided by the average of the quarterly average shareholders’ equity balances.

[b] Dividend payout ratio is calculated as dividends paid divided by beginning shareholders’ equity.

[c] Total return to shareholders is calculated as the change in diluted book value per share plus the dividend payout ratio.

20

ALTERRA CAPITAL HOLDINGS LIMITED

EARNINGS PER SHARE INFORMATION (Unaudited)

(Expressed in thousands of United States Dollars, except per share and share amounts)

	FOR THE QUARTERS ENDED
	Mar. 31, 2011			Mar. 31, 2010
Net (loss) income available to common shareholders	$	(46,687	)	$	36,381
Denominator:
Weighted average shares - basic
Outstanding [a]		106,978,358			56,112,672
Unvested restricted share units		186,870			403,921
		107,165,228			56,516,593
Share equivalents:
Warrants		—			632,465
Options		—			234,690
Employee stock purchase plan		—			—
Non participating restricted shares		—			—
Weighted average shares - diluted [b]		107,165,228			57,383,748
Basic earnings per share	$	(0.44	)	$	0.64
Diluted earnings per share	$	(0.44	)	$	0.63

[a] Includes weighted average unvested participating restricted shares

[b] Computed using the treasury method. The treasury method assumes that the proceeds received from the exercise of options or warrants will be used to repurchase the Company’s common shares at the average market price during the period of calculation.

21

ALTERRA CAPITAL HOLDINGS LIMITED

OPERATING INCOME RECONCILIATION (Unaudited)

(Expressed in thousands of United States Dollars, except per share and share amounts)

	FOR THE QUARTERS ENDED
	Mar. 31, 2011			Mar. 31, 2010
Before tax
Net (loss) income	$	(49,387	)	$	38,346
Net realized and unrealized losses on non-hedge fund investments, before tax [a]		23,109			1,368
Foreign exchange gains, before tax		(878	)		(2,452	)
Merger and acquisition expenses, before tax		—			4,744
Net operating (loss) income		(27,156	)		42,006
Net of tax
Net (loss) income	$	(46,687	)	$	36,381
Net realized and unrealized losses on non-hedge fund investments, net of tax [a]		22,602			1,236
Foreign exchange gains, net of tax		(640	)		(1,680	)
Merger and acquisition expenses, net of tax		—			4,744
Net operating (loss) income		(24,725	)		40,681
Weighted average shares outstanding:
Basic		107,165,228			56,516,593
Diluted		107,165,228			57,383,748
Basic per share data
Earnings per share	$	(0.44	)	$	0.64
Net realized and unrealized losses on non-hedge fund investments, net of tax [a]		0.21			0.02
Foreign exchange gains, net of tax		(0.01	)		(0.03	)
Merger and acquisition expenses, net of tax		—			0.09
Net operating (loss) income per share	$	(0.23	)	$	0.72
Diluted per share data
Diluted earnings per share	$	(0.44	)	$	0.63
Net realized and unrealized losses on non-hedge fund investments, net of tax [a]		0.21			0.02
Foreign exchange gains, net of tax		(0.01	)		(0.03	)
Merger and acquisition expenses, net of tax		—			0.09
Net operating (loss) income per diluted share	$	(0.23	)	$	0.71

[a] Net realized and unrealized (gains) losses on non-hedge fund investments includes realized and unrealized (gains) losses on trading securities, realized (gains) losses on available for sale securities, net impairment losses recognized in earnings, earnings from equity method investments and changes in fair value of investment derivatives, catastrophe bonds and structured deposits.

Per share totals may not add due to rounding.

22

ALTERRA CAPITAL HOLDINGS LIMITED

BOOK VALUE PER SHARE (Unaudited)

(Expressed in thousands of United States Dollars, except per share and share amounts)

	As of Mar. 31, 2011		As of Dec. 31, 2010
Price per share at period end	$	22.26	$	21.64
Shareholders’ equity	$	2,723,194	$	2,918,270
Goodwill and intangible assets	$	58,585	$	59,076
Tangible book value	$	2,664,609	$	2,859,194
Basic common shares outstanding [a]		105,733,610		110,963,160
Add: unvested restricted stock units		247,179		167,971
Add: dilutive impact of warrants outstanding		1,346,672		1,036,442
Add: dilutive impact of options outstanding		134,901		123,395
Add: dilutive impact of employee stock purchase plan		4,016		—
Diluted shares outstanding [b]		107,466,378		112,290,968
Basic book value per share	$	25.76	$	26.30
Diluted book value per share	$	25.34	$	25.99
Basic tangible book value per share	$	25.20	$	25.77
Diluted tangible book value per share	$	24.79	$	25.46

[a] Includes unvested restricted shares

[b] Computed using the treasury method. The treasury method assumes that the proceeds received from the exercise of options or warrants will be used to repurchase the Company’s common shares at the period-end market price.

23

ALTERRA CAPITAL HOLDINGS LIMITED

REGULATION G

In presenting the Company’s results, management has included and discussed net operating income, net operating income per share, net operating income per diluted share, annualized net operating return on average shareholders’ equity, tangible book value per share and diluted tangible book value per share. These measures are “non-GAAP financial measures” as defined in Regulation G. Management believes that these non-GAAP financial measures, which may be defined differently by other companies, allow for a more complete understanding of the Company’s business. These measures, however, should not be viewed as a substitute for those determined in accordance with U.S. GAAP. The reconciliation of such measures to their respective most directly comparable U.S. GAAP financial measures is presented in the attached financial information in accordance with Regulation G.

Net operating income is defined as net income excluding after-tax net realized and unrealized gains or losses on non- hedge fund investments (this includes net realized and unrealized gains or losses on trading securities, net realized gains or losses on available for sale securities, net impairment losses recognized in earnings, changes in fair value of investment derivatives, catastrophe bonds, structured deposits and earnings from equity method investments), after-tax net foreign exchange gains or losses and after-tax merger and acquisition expenses. Net operating income per share and per diluted share is defined as the net operating income divided by the weighted average common shares or weighted average diluted common shares, respectively. We believe that this non-GAAP measure provides a better indication of management performance as realized and unrealized gains and losses on fixed maturities may fluctuate from period to period and foreign exchange gains and losses are typically outside the control of management. Merger and acquisition expenses are not indicative of expenses fundamental to the business and may fluctuate from period to period.

Annualized net operating return on average shareholders’ equity is defined as annualized net operating income divided by the average of the beginning and ending shareholders’ equity. Tangible book value is defined as shareholders’ equity excluding goodwill and intangible assets. Tangible book value per share and diluted tangible book value per share is defined as the tangible book value divided by the common shares outstanding or diluted common shares outstanding, respectively. These non-GAAP measures allow management to assess how the Company has performed in terms of wealth generated for its shareholders.

24

ALTERRA CAPITAL HOLDINGS LIMITED

Reclassified Segment Information

Selected Financial Information

25

ALTERRA CAPITAL HOLDINGS LIMITED

RECLASSIFICATION OF INSURANCE AND U.S. SPECIALTY SEGMENTS

(Expressed in thousands of United States Dollars)

INSURANCE SEGMENT

	Year ended						Year ended			Year ended						Year ended
	Dec. 31, 2010						Dec. 31, 2010			Dec. 31, 2009						Dec. 31, 2009
	(Reclassified)						(As previously reported)			(Reclassified)						(As previously reported)
Gross premiums written	$	399,612		$	29,492		$	370,120		$	447,340		$	19,573		$	427,767
Reinsurance premiums ceded		(180,691	)		(10,083	)		(170,608	)		(218,633	)		(6,550	)		(212,083	)
Net premiums written	$	218,921		$	19,409		$	199,512		$	228,707		$	13,023		$	215,684
Earned premiums	$	415,396		$	23,680		$	391,716		$	434,147		$	17,057		$	417,090
Earned premiums ceded		(180,684	)		(7,561	)		(173,123	)		(216,687	)		(5,560	)		(211,127	)
Net premiums earned		234,712			16,119			218,593			217,460			11,497			205,963
Net losses and loss expenses		(140,108	)		(11,285	)		(128,823	)		(140,403	)		(8,048	)		(132,355	)
Acquisition costs		(3,651	)		(270	)		(3,381	)		1,206			(27	)		1,233
General and administrative expenses		(34,508	)		(5,893	)		(28,615	)		(27,927	)		(3,304	)		(24,623	)
Other income		1,267			507			760			1,620			382			1,238
Underwriting income (loss)	$	57,712		$	(822	)	$	58,534		$	51,956		$	500		$	51,456
Loss ratio		59.7	%					58.9	%		64.6	%					64.3	%
Acquisition cost ratio		1.6	%					1.6	%		(0.6	%)					(0.6	%)
General and administrative expense ratio		14.7	%					13.1	%		12.9	%					11.9	%
Combined ratio		76.0	%					73.6	%		76.9	%					75.6	%

U.S. SPECIALTY SEGMENT

	Year ended						Year ended			Year ended						Year ended
	Dec. 31, 2010						Dec. 31, 2010			Dec. 31, 2009						Dec. 31, 2009
	(Reclassified)						(As previously reported)			(Reclassified)						(As previously reported)
Gross premiums written	$	294,498		$	(29,492	)	$	323,990		$	265,905		$	(19,573	)	$	285,478
Reinsurance premiums ceded		(88,493	)		10,083			(98,576	)		(148,546	)		6,550			(155,096	)
Net premiums written	$	206,005		$	(19,409	)	$	225,414		$	117,359		$	(13,023	)	$	130,382
Earned premiums	$	288,270		$	(23,680	)	$	311,950		$	239,613		$	(17,057	)	$	256,670
Earned premiums ceded		(117,657	)		7,561			(125,218	)		(149,008	)		5,560			(154,568	)
Net premiums earned		170,613			(16,119	)		186,732			90,605			(11,497	)		102,102
Net losses and loss expenses		(107,052	)		11,285			(118,337	)		(54,764	)		8,048			(62,812	)
Acquisition costs		(28,174	)		270			(28,444	)		(7,474	)		27			(7,501	)
General and administrative expenses		(30,122	)		5,893			(36,015	)		(27,925	)		3,304			(31,229	)
Other income		—			(507	)		507			(68	)		(382	)		314
Underwriting income (loss)	$	5,265		$	822		$	4,443		$	374		$	(500	)	$	874
Loss ratio		62.7	%					63.4	%		60.4	%					61.5	%
Acquisition cost ratio		16.5	%					15.2	%		8.2	%					7.3	%
General and administrative expense ratio		17.7	%					19.3	%		30.9	%					30.7	%
Combined ratio		96.9	%					97.9	%		99.5	%					99.5	%

Effective January 1, 2011, Alterra redefined its Insurance and U.S. Specialty segments based on changes to the internal reporting structure. Insurance business underwritten by Alterra Insurance USA Inc., which was previously reported within the U.S. Specialty segment, has been reclassified to the Insurance segment. Alterra Insurance USA Inc. is a managing general underwriter for Alterra Excess & Surplus Insurance Company and Alterra America Insurance Company, as well as various third party insurance companies, and is Alterra’s principal insurance underwriting platform for retail distribution in the United States. Segment disclosures for comparative periods have been restated to reflect this reclassification.

26

ALTERRA CAPITAL HOLDINGS LIMITED

INSURANCE SEGMENT Results - as Reclassified (Unaudited)

(Expressed in thousands of United States Dollars)

	Dec. 31, 2010			Sept. 30, 2010			June 30, 2010			Mar. 31, 2010			Dec. 31, 2009			Sept. 30, 2009			June 30, 2009			Mar. 31, 2009
Gross premiums written	$	113,236		$	77,944		$	139,026		$	69,406		$	126,678		$	90,430		$	139,226		$	91,006
Reinsurance premiums ceded		(56,728	)		(36,875	)		(47,437	)		(39,651	)		(71,053	)		(43,388	)		(47,972	)		(56,220	)
Net premiums written	$	56,508		$	41,069		$	91,589		$	29,755		$	55,625		$	47,042		$	91,254		$	34,786
Earned premiums	$	106,169		$	102,640		$	104,841		$	101,746		$	114,155		$	108,776		$	105,576		$	105,640
Earned premiums ceded		(43,847	)		(42,796	)		(45,211	)		(48,830	)		(56,043	)		(56,337	)		(51,129	)		(53,178	)
Net premiums earned		62,322			59,844			59,630			52,916			58,112			52,439			54,447			52,462
Net losses and loss expenses		(35,687	)		(26,679	)		(38,296	)		(39,446	)		(27,829	)		(34,515	)		(39,901	)		(38,158	)
Acquisition costs		(1,765	)		(1,382	)		(821	)		317			(60	)		(331	)		230			1,367
General and administrative expenses		(11,812	)		(7,717	)		(8,132	)		(6,847	)		(7,046	)		(8,114	)		(6,693	)		(6,074	)
Other income		68			1,108			97			(6	)		42			143			219			1,216
Underwriting income	$	13,126		$	25,174		$	12,478		$	6,934		$	23,219		$	9,622		$	8,302		$	10,813
Loss ratio		57.3	%		44.6	%		64.2	%		74.5	%		47.9	%		65.8	%		73.3	%		72.7	%
Acquisition cost ratio		2.8	%		2.3	%		1.4	%		(0.6	%)		0.1	%		0.6	%		(0.4	%)		(2.6	%)
General and administrative expense ratio		18.9	%		12.9	%		13.6	%		13.0	%		12.1	%		15.5	%		12.3	%		11.6	%
Combined ratio		79.0	%		59.8	%		79.2	%		86.9	%		60.1	%		81.9	%		85.2	%		81.7	%

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ALTERRA CAPITAL HOLDINGS LIMITED

U.S. SPECIALTY SEGMENT Results - as Reclassified (Unaudited)

(Expressed in thousands of United States Dollars)

	Dec. 31, 2010			Sept. 30, 2010			June 30, 2010			Mar. 31, 2010			Dec. 31, 2009			Sept. 30, 2009			June 30, 2009			Mar. 31, 2009
Gross premiums written	$	65,625		$	64,198		$	90,773		$	73,902		$	64,572		$	60,123		$	75,701		$	65,509
Reinsurance premiums ceded		(15,956	)		(18,713	)		(5,672	)		(48,152	)		(31,471	)		(24,755	)		(52,938	)		(39,382	)
Net premiums written	$	49,669		$	45,485		$	85,101		$	25,750		$	33,101		$	35,368		$	22,763		$	26,127
Earned premiums	$	74,683		$	73,337		$	71,065		$	69,185		$	66,287		$	63,360		$	59,053		$	50,913
Earned premiums ceded		(26,140	)		(26,071	)		(27,053	)		(38,393	)		(40,260	)		(35,551	)		(41,271	)		(31,926	)
Net premiums earned		48,543			47,266			44,012			30,792			26,027			27,809			17,782			18,987
Net losses and loss expenses		(31,878	)		(29,295	)		(26,683	)		(19,196	)		(14,809	)		(18,507	)		(11,057	)		(10,391	)
Acquisition costs		(8,618	)		(6,763	)		(9,111	)		(3,682	)		(1,838	)		(1,964	)		(2,483	)		(1,189	)
General and administrative expenses		(7,552	)		(8,693	)		(6,355	)		(7,522	)		(9,786	)		(6,971	)		(4,357	)		(6,811	)
Other income		—			—			—			—			—			—			153			(221	)
Underwriting income (loss)	$	495		$	2,515		$	1,863		$	392		$	(406	)	$	367		$	38		$	375
Loss ratio		65.7	%		62.0	%		60.6	%		62.3	%		56.9	%		66.6	%		62.2	%		54.7	%
Acquisition cost ratio		17.8	%		14.3	%		20.7	%		12.0	%		7.1	%		7.1	%		14.0	%		6.3	%
General and administrative expense ratio		15.5	%		18.4	%		14.5	%		24.4	%		37.6	%		25.0	%		24.4	%		35.9	%
Combined ratio		99.0	%		94.7	%		95.8	%		98.7	%		101.6	%		98.7	%		100.6	%		96.9	%

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ALTERRA CAPITAL HOLDINGS LIMITED

Pro Forma Combined - Alterra Capital Holdings Limited and Harbor Point Limited

Selected Financial Information

The following presentation is for informational purposes only

29

ALTERRA CAPITAL HOLDINGS LIMITED

PRO FORMA COMBINED STATEMENTS OF INCOME [a] (unaudited)

(Expressed in thousands of United States Dollars)

	FOR THE QUARTERS ENDED
	June 30, 2010			Mar. 31, 2010			Dec. 31, 2009			Sept. 30, 2009			June 30, 2009			Mar. 31, 2009
REVENUES
Gross premiums written	$	476,550		$	676,905		$	337,048		$	382,650		$	564,251		$	662,432
Reinsurance premiums ceded		(81,333	)		(159,515	)		(81,627	)		(73,703	)		(126,503	)		(168,155	)
Net premiums written	$	395,217		$	517,390		$	255,421		$	308,947		$	437,748		$	494,277
Net premiums earned	$	368,061		$	338,332		$	347,833		$	351,245		$	366,130		$	317,598
Net investment income		61,562			64,583			60,668			60,068			59,636			58,943
Net realized and unrealized (losses) gains on investments		(13,734	)		13,280			18,004			29,622			22,462			20,722
Net impairment losses recognized in earnings		(300	)		(420	)		(925	)		(139	)		(2,014	)		—
Net realized gain on retirement of senior notes		—			—			111			—			—			—
Other income		339			480			189			964			1,193			1,799
Total revenues		415,928			416,255			425,880			441,760			447,407			399,062
LOSSES AND EXPENSES
Net losses and loss expenses		213,517			210,543			166,573			181,064			186,301			178,130
Claims and policy benefits		13,943			17,659			16,976			14,378			55,407			14,332
Acquisition costs		64,315			53,998			54,042			59,613			53,317			47,611
Interest expense		8,061			5,226			6,978			6,292			5,146			4,351
Net foreign exchange (gains) losses		(1,622	)		(869	)		789			(116	)		(5,571	)		(1,911	)
Merger and acquisition expenses		—			—			—			(41,350	)		4,785			5,223
General and administrative expenses		60,137			51,611			66,157			57,048			53,979			57,508
Total losses and expenses		358,351			338,168			311,515			276,929			353,364			305,244
INCOME BEFORE TAXES		57,577			78,087			114,365			164,831			94,043			93,818
Income tax expense		4,294			1,311			5,686			2,910			3,206			1,990
NET INCOME		53,283			76,776			108,679			161,921			90,837			91,828

[a] The information presented above is on a combined pro forma basis (after the elimination of intercompany transactions and the amortization of certain acquisition accounting fair value adjustments). The pro forma financial information is provided for informational purposes only, to present a summary of the combined results of operations assuming the amalgamation with Harbor Point had occurred at the beginning of each calendar year presented. The pro forma data does not necessarily represent results that would have occurred if the amalgamation had taken place at the beginning of each calendar year presented, nor is it necessarily indicative of the future results.

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