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Exhibit 12

ASSURED GUARANTY LTD.
COMPUTATION OF RATIO OF EARNINGS TO FIXED CHARGES
(in millions of U.S. dollars except for ratio amounts)

		2003		2004		2005		2006		2007			Six Months Ended June 30, 2008
Income (loss) before income taxes		$	246.2	$	233.3	$	229.6	$	190.0	$	(463.0	)	$	521.7
Fixed charges			6.9		11.8		14.5		14.8		24.7			12.2
Income (loss) as adjusted			253.1		245.1		244.1		204.8		(438.3	)		533.9
Fixed charges:
	Interest expensed		5.7		10.7		13.5		13.8		23.5			11.6
	Portion of rents representative of the interest factor		1.2		1.1		1.0		1.0		1.2			0.6
Total fixed charges			6.9		11.8		14.5		14.8		24.7			12.2
Ratio of earnings to fixed charges			36.49		20.85		16.83		13.84		(17.74	)		43.76

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Exhibit 12

ASSURED GUARANTY LTD. COMPUTATION OF RATIO OF EARNINGS TO FIXED CHARGES (in millions of U.S. dollars except for ratio amounts)