Exhibit 12.1

Schedule of Computation of Ratio of Earnings to Fixed Charges

	Years Ended December 31,
	2008		2009			2010			2011		2012
Earnings:
Income (loss) before income taxes and cumulative effect of accounting change	$	104,538	$	(41,848	)	$	(20,804	)	$	53,969	$	116,453
Interest expense		35,903		55,857			72,307			86,192		93,200
(Gain)/loss on investment in equity investees in excess of distributed earnings		—		164			2,243			—		361
Amortization of capitalized interest		—		152			267			170		115
Loan cost amortization		—		—			—			523		2,906
Earnings	$	140,441	$	14,325		$	54,013		$	140,854	$	213,035
Fixed Charges:
Interest expense	$	35,903	$	55,857		$	72,307		$	86,192	$	93,200
Capitalized interest		2,040		2,764			593			883		2,249
Loan cost amortization		—		—			—			523		2,906
Fixed Charges	$	37,943	$	58,621		$	72,900		$	87,598	$	98,355
Ratio of Earnings to Fixed Charges		3.7		0.2			0.7			1.6		2.2
Insufficient Coverage	$	—	$	44,296		$	18,887		$	—	$	—