Exhibit 12.1

Computation of Ratio of Earnings to Fixed Charges

	Year ended
												Three Months Ended
	31-Dec		31-Dec			31-Dec		31-Dec		31-Dec		31-Mar
	2005		2006			2007		2008		2009		2010
Consolidated Statements of Income Data
Income (loss) before income taxes	$	60,140		($22,227	)	$	93,934	$	81,026	$	143,146	$	70
Add:
Portion of rents representative of the interest factor	$	974	$	968		$	973	$	2,347	$	2,287	$	553
Interest on indebtedness		12,709		23,437			27,591		21,525		17,530		5,156
Amortization of deferred financing costs		374		1,016			1,431		1,635		1,637		506
Income as adjusted	$	74,197	$	3,194		$	123,929	$	106,533	$	164,600	$	6,285
Fixed charges:
Portion of rents representative of the interest factor	$	974	$	968		$	973	$	2,347	$	2,287	$	553
Interest of indebtedness		12,709		23,437			27,591		21,525		17,530		5,156
Amortization of deferred financing costs		374		1,016			1,431		1,635		1,637	$	506
Fixed charges	$	14,057	$	25,421		$	29,995	$	25,507	$	21,454	$	6,215
Ratio of earnings to fixed charges		5.3x		(*)			4.1x		4.2x		7.7x		1.0x

* Earnings were insufficient to cover fixed charges by $22.2 million.