Arch Capital (ACGL) 10-K 2009 FY Annual report

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Exhibit 12

Arch Capital Group Ltd. and Subsidiaries
Computation of Ratio of Earnings to Fixed Charges and Preference Dividends
(in thousands, except ratios)

		Years Ended December 31,
		2009			2008		2007			2006			2005
Income before income taxes		$	897,653		$	304,505	$	873,544		$	739,893		$	285,435
	Equity in net (income) loss of investees		(187,835	)		166,326		(8,877	)		(3,102	)		—
	Fixed charges		30,074			29,673		27,032			26,386			26,204
Income available for fixed charges		$	739,892		$	500,504	$	891,699		$	763,177		$	311,639
Fixed charges:
	Interest and amortization on indebtedness		24,440			23,838		22,093			22,090			22,504
	Estimate of interest component within rental expense net of sublease (income)(1)		5,634			5,835		4,939			4,296			3,700
Total fixed charges			30,074			29,673		27,032			26,386			26,204
Preference dividends			25,844			25,844		25,844			20,655			—
Total fixed charges and preference dividends			55,918			55,517		52,876			47,041			26,204
Ratio of earnings to fixed charges			24.6			16.9		33.0			28.9			11.9
Ratio of earnings to fixed charges and preference dividends			13.2			9.0		16.9			16.2			11.9

(1)

Represents a reasonable approximation of the interest cost component of rental expense net of sublease (income) incurred by the Company.

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Exhibit 12

Arch Capital Group Ltd. and Subsidiaries Computation of Ratio of Earnings to Fixed Charges and Preference Dividends (in thousands, except ratios)