CSK Auto (CAO) S-3ASR Automatic shelf registration

Exhibit 12.1

O’Reilly Automotive, Inc.

Computation of Ratio of Earnings to Fixed Charges

	Six Months Ended June  30,						Fiscal Year
	2011			2010			2010			2009			2008			2007			2006
Earnings
Income before income taxes	$	383,156		$	329,921		$	689,373		$	496,898		$	302,532		$	307,488		$	282,265
Fixed charges		58,112			68,305			132,210			138,920			83,266			27,590			25,920
Less: Capitalized interest		(2,378	)		(2,886	)		(5,133	)		(6,715	)		(2,318	)		(2,554	)		(2,639	)
Adjusted earnings	$	438,890		$	395,340		$	816,450		$	629,103		$	383,480		$	332,524		$	305,546
Fixed charges
Interest expense	$	13,342		$	20,633		$	35,847		$	43,383		$	24,372		$	6,197		$	6,864
Amortization of debt issuance costs		530			4,278			8,559			8,508			4,084			80			97
Interest portion of rent expense		44,240			43,394			87,804			87,029			54,810			21,313			18,959
Total fixed charges	$	58,112		$	68,305		$	132,210		$	138,920		$	83,266		$	27,590		$	25,920
Ratio of earnings to fixed charges		7.6			5.8			6.2			4.5			4.6			12.1			11.8