Archrock (AROC) 8-K Entry into a Material Definitive Agreement

Exhibit 12.1

EXTERRAN HOLDINGS, INC.

	Three Months Ended March 31,						Years Ended December 31,
	2009			2008			2008 (1)			2007			2006			2005 (2)			2004 (3)
	( $ in thousands)
Income (loss):
Income (loss) from continuing operations before income taxes	$	(40,809	)	$	81,593		$	(898,277	)	$	52,770		$	114,504		$	(9,434	)	$	(29,324	)
Add:
Interest on indebtedness, amortization of capitalized interest and amortization of capitalized debt expense and discount		16,681			(57,382	)		(7,446	)		89,054			124,274			147,796			158,241
Leasing expense and the estimated interest factor attributable to rents		8,005			48,417			72,527			24,051			4,075			3,234			3,450
Subtract:
Equity in (income) loss of non-consolidated affiliate in excess of distributions of income		91,117			(6,093	)		(20,669	)		(3,982	)		(1,831	)		(2,783	)		(10,112	)
Income (loss) as adjusted		74,944			66,535			(853,865	)		161,893			241,022			138,813			122,255
Fixed charges:
Interest on indebtedness, amortization of capitalized expenses and discount and capitalized interest		22,800			(12,322	)		60,468			110,200			125,339			147,344			157,502
Leasing expense and the estimated interest factor attributable to rents		8,005			48,417			72,527			24,051			4,075			3,234			3,450
Total fixed charges		30,805			36,095			132,995			134,251			129,414			150,578			160,952
Ratio of earnings to fixed charges		2.43			1.84			—			1.21			1.86			—			—

(1)	Due to its loss for the year ended December 31, 2008, the ratio was less than 1:1. Exterran Holdings, Inc., together with its subsidiaries (“we,” “us,” “our,” or “Exterran”), would have had to generate additional pre-tax earnings of $986.9 million to achieve coverage of 1:1. In the fourth quarter of 2008, we recorded a goodwill impairment charge of $1,148.4 million and an impairment charge of $21.6 million to reduce the carrying amount of our assets associated with the Cawthorne Channel Project to their estimated fair value. For more information regarding these pre-tax charges, see Notes 9 and 20, respectively, to the consolidated financial statements included in our Current Report on Form 8-K dated June 3, 2009.
(2)	Due to Exterran’s loss for the year ended December 31, 2005, the ratio was less than 1:1. Exterran would have had to generate additional pre-tax earnings of $11.8 million to achieve coverage of 1:1. During the year, we recorded $9.8 million in pre-tax charges. For a description of these pre-tax charges, see Note 22 in the notes to the consolidated financial statements included in Hanover Compressor Company’s (“Hanover”) Annual Report on Form 10-K for the year ended December 31, 2005.
(3)	Due to Exterran’s loss for the year ended December 31, 2004, the ratio was less than 1:1. Exterran would have had to generate additional pre-tax earnings of $38.7 million to achieve coverage of 1:1. During the year, we recorded $0.4 million in pre-tax benefit. For a description of this pre-tax benefit, see Note 22 in the notes to the consolidated financial statements included in Hanover’s Annual Report on Form 10-K for the year ended December 31, 2005.

Computation of Pro Forma Ratio of Earnings to Fixed Charges After Adjustment for Issuance of
Convertible Senior Notes

			Year Ended
	Three Months Ended		December 31,
	March 31, 2009		2008 (4)
Income (loss):
Income (loss) as adjusted, as above	$	74,993	$	(853,869	)
Fixed charges, as above		30,805		132,995
Adjustments:
Estimated net increase in interest expense from refinancing		5,788		18,491
Total pro forma fixed charges		36,593		151,487
Pro forma ratio of earnings to fixed charges		2.0		—

(4) Due to Exterran’s loss for the year ended December 31, 2008, the ratio was less than 1:1. Exterran would have had to generate additional pre-tax earnings of $1,005.4 million to achieve coverage of 1:1.