Exhibit 12.1

Computation of Ratio of Earnings to Fixed Charges

The following table sets forth our ratio of earnings to fixed charges for the periods indicated. All amounts are in thousands, except for the ratio of earnings to fixed charges.

	Six Months Ended June 30,			Year Ended December 31,
	2013			2012			2011			2010			2009		2008
	(in thousands)
Income before income taxes	$	407,990		$	789,692		$	760,009		$	609,473		$	493,489	$	474,201
Interest expense		19,849			38,902			34,533			30,541			23,643		18,889
(Net income)/loss attributable to noncontrolling interest		(6,277	)		(10,161	)		(12,068	)		(9,469	)		1,834		0
Adjusted Earnings	$	421,562		$	818,433		$	782,474		$	630,545		$	518,966	$	493,090
Fixed Charges	$	19,849		$	38,902		$	34,533		$	30,541		$	23,643	$	18,889
Ratio of Earnings to Fixed Charges		21.2x			21.0x			22.7x			20.6x			22.0x		26.1x