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Exhibit 12.1

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

 
  2004   2005   2006   2007   2008   Three Months
Ended
March 31, 2009
 

Income (loss) before income taxes

  $ 233.3   $ 229.6   $ 190.0   $ (463.0 ) $ 112.3   $ 100.1  

Fixed charges

    11.8     14.5     14.8     24.7     25.2     6.6  

Income (loss) as adjusted

    245.1     244.1     204.8     (438.3 )   137.5     106.7  

Fixed charges:

                                     
 

Interest expensed

    10.7     13.5     13.8     23.5     23.3     5.8  
 

Portion of rents representative of the interest factor

    1.1     1.0     1.0     1.2     1.9     0.8  

Total fixed charges

    11.8     14.5     14.8     24.7     25.2     6.6  
                           

Ratio of earnings to fixed charges

    20.85     16.83     13.84     (17.74 )   5.46     16.17  
                           



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