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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)

 
  2005   2006   2007   2008   2009  

Income (loss) before income taxes

  $ 229.6   $ 190.0   $ (463.0 ) $ 112.3   $ 132.9  

Fixed charges

    14.5     14.8     24.7     25.2     66.3  

Income (loss) as adjusted

    244.1     204.8     (438.3 )   137.5     199.2  

Fixed charges:

                               
 

Interest expensed

    13.5     13.8     23.5     23.3     62.8  
 

Portion of rents representative of the interest factor (all premises)

                            3.5  
 

Portion of rents representative of the interest factor (1251 Ave of Am)

                      0.7        
 

Portion of rents representative of the interest factor (1325 Ave of Am)

    1.0     1.0     1.2     1.2        

Total fixed charges

    14.5     14.8     24.7     25.2     66.3  
                       

Ratio of earnings to fixed charges

    16.83     13.84     (17.74 )   5.46     3.00  
                       



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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)