Exhibit 12.1

COMPUTATION OF RATIO OF EARNINGS TO FIXED CHARGES



|                                             |  |                          |         |                          |   |          |                          |  |                          |         |                          |   |         |  |   |       
|-------------------------------------------- |  | ------------------------ | ------- | ------------------------ | - | -------- | ------------------------ |  | ------------------------ | ------- | ------------------------ | - | ------- |  | - | ------
|(in thousands of U.S. dollars,except ratios) |  | Year EndDecember 31,2009 |         | Year EndDecember 31,2008 |   |          | Year EndDecember 31,2007 |  | Year EndDecember 31,2006 |         | Year EndDecember 31,2005
|Earnings:                                    |  |                          |         |                          |   |          |                          |  |                          |         |                          |   |         |  |   |       
|Pre-tax income (loss)                        |  | $                        | 246,215 |                          | $ | (174,086 | )                        |  | $                        | 302,827 |                          | $ | 217,988 |  | $ | 10,477
|Fixed charges                                |  |                          | 23,260  |                          |   | 37,462   |                          |  |                          | 43,562  |                          |   | 14,503  |  |   | 23,235
|                                             |  |                          |         |                          |   |          |                          |  |                          |         |                          |   |         |  |   |       
|Total Earnings (Loss)                        |  | $                        | 269,475 |                          | $ | (136,624 | )                        |  | $                        | 346,389 |                          | $ | 232,491 |  | $ | 33,712
|                                             |  |                          |         |                          |   |          |                          |  |                          |         |                          |   |         |  |   |       
|Fixed Charges:                               |  |                          |         |                          |   |          |                          |  |                          |         |                          |   |         |  |   |       
|Interest and amortization on indebtedness    |  | $                        | 21,453  |                          | $ | 36,143   |                          |  | $                        | 42,702  |                          | $ | 13,832  |  | $ | 22,764
|Rental expense at 33.3%(1)                   |  |                          | 1,807   |                          |   | 1,319    |                          |  |                          | 860     |                          |   | 671     |  |   | 471   
|                                             |  |                          |         |                          |   |          |                          |  |                          |         |                          |   |         |  |   |       
|Total Fixed Charges                          |  | $                        | 23,260  |                          | $ | 37,462   |                          |  | $                        | 43,562  |                          | $ | 14,503  |  | $ | 23,235
|                                             |  |                          |         |                          |   |          |                          |  |                          |         |                          |   |         |  |   |       
|Ratio of Earnings to Fixed Charges           |  |                          | 11.6    |                          |   | (3.7     | )                        |  |                          | 8.0     |                          |   | 16.0    |  |   | 1.5   
|                                             |  |                          |         |                          |   |          |                          |  |                          |         |                          |   |         |  |   |       
|Deficiency                                   |  |                          | N/A     |                          | $ | 174,086  |                          |  |                          | N/A     |                          |   | N/A     |  |   | N/A   
|                                             |  |                          |         |                          |   |          |                          |  |                          |         |                          |   |         |  |   |       



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