Exhibit 12.1

COMPUTATION OF RATIO OF EARNINGS TO FIXED CHARGES



|                                              |  |                               |         |                           |   |          |                           |  |                           |         |                           |   |                           |  |   |        |  |   |        
|--------------------------------------------- |  | ----------------------------- | ------- | ------------------------- | - | -------- | ------------------------- |  | ------------------------- | ------- | ------------------------- | - | ------------------------- |  | - | ------ |  | - | -------
|(in thousands of U.S. dollars, except ratios) |  | Six Months EndedJune 30, 2009 |         | Year EndDecember 31, 2008 |   |          | Year EndDecember 31, 2007 |  | Year EndDecember 31, 2006 |         | Year EndDecember 31, 2005 |   | Year EndDecember 31, 2004
|Earnings:                                     |  |                               |         |                           |   |          |                           |  |                           |         |                           |   |                           |  |   |        |  |   |        
|                                              |  |                               |         |                           |   |         
|Pre-tax income (loss)                         |  | $                             | 92,134  |                           | $ | (174,086 | )                         |  | $                         | 302,827 |                           | $ | 217,988                   |  | $ | 10,477 |  | $ | 141,754
|Fixed charges                                 |  |                               | 9,571   |                           |   | 37,462   |                           |  |                           | 43,562  |                           |   | 14,503                    |  |   | 23,235 |  |   | 21,190 
|                                              |  |                               |         |                           |   |          |                           |  |                           |         |                           |   |                           |  |   |        |  |   |        
|                                              |  |                               |         |                           |   |         
|Total Earnings (Loss)                         |  | $                             | 101,705 |                           | $ | (136,624 | )                         |  | $                         | 346,389 |                           | $ | 232,491                   |  | $ | 33,712 |  | $ | 162,944
|                                              |  |                               |         |                           |   |          |                           |  |                           |         |                           |   |                           |  |   |        |  |   |        
|                                              |  |                               |         |                           |   |         
|Fixed Charges:                                |  |                               |         |                           |   |          |                           |  |                           |         |                           |   |                           |  |   |        |  |   |        
|                                              |  |                               |         |                           |   |         
|Interest and amortization on indebtedness     |  | $                             | 8,709   |                           | $ | 36,143   |                           |  | $                         | 42,702  |                           | $ | 13,832                    |  | $ | 22,764 |  | $ | 20,644 
|Rental expense at 33.3% (1)                   |  |                               | 822     |                           |   | 1,319    |                           |  |                           | 860     |                           |   | 671                       |  |   | 471    |  |   | 546    
|                                              |  |                               |         |                           |   |          |                           |  |                           |         |                           |   |                           |  |   |        |  |   |        
|                                              |  |                               |         |                           |   |         
|Total Fixed Charges                           |  | $                             | 9,571   |                           | $ | 37,462   |                           |  | $                         | 43,562  |                           | $ | 14,503                    |  | $ | 23,235 |  | $ | 21,190 
|                                              |  |                               |         |                           |   |          |                           |  |                           |         |                           |   |                           |  |   |        |  |   |        
|                                              |  |                               |         |                           |   |         
|Ratio of Earnings to Fixed Charges            |  |                               | 10.6    |                           |   | (3.7     | )                         |  |                           | 8.0     |                           |   | 16.0                      |  |   | 1.5    |  |   | 7.7    
|                                              |  |                               |         |                           |   |          |                           |  |                           |         |                           |   |                           |  |   |        |  |   |        
|                                              |  |                               |         |                           |   |         
|Deficiency                                    |  |                               | N/A     |                           | $ | 174,086  |                           |  |                           | N/A     |                           |   | N/A                       |  |   | N/A    |  |   | N/A    
|                                              |  |                               |         |                           |   |          |                           |  |                           |         |                           |   |                           |  |   |        |  |   |        



|(1) | 33.3% represents a reasonable approximation of the interest factor
|--- | ------------------------------------------------------------------



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