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Exhibit 12

Ratio of Earnings to Fixed Charges Worksheet
(In Thousands)

													Three Months Ended March 31,
	Year Ended December 31,
Ratio of Earnings to Fixed Charges
	1999		2000		2001			2002		2003			2003			2004
Fixed Charges:
Interest on debt and capitalized leases	$	35,111	$	64,980	$	55,085		$	46,784	$	35,771		$	9,121		$	6,026
Amortization of debt discount and expense		675		3,931		3,261			3,417		3,098			898			486
Interest element of rentals (a)		10,823		7,089		6,716			6,798		6,171			1,693			1,591
Total Fixed Charges	$	46,609	$	76,000	$	65,062		$	56,999	$	45,040		$	11,712		$	8,103
Earnings:
Consolidated net income (loss)	$	33,005	$	64,180	$	(12,043	)	$	31,195	$	12,495		$	(1,674	)	$	18,738
Addback:
Loss from discontinued operation of the methanol business, net of tax		10,156		—		—			—		—			—			—
Consolidated provision for income taxes		24,808		36,112		(14,918	)		17,546		5,245			(941	)		11,123
Fixed charges less interest capitalized		45,661		74,829		64,033			56,377		44,314			11,585			7,859
Subtotal Earnings		113,630		175,121		37,072			105,118		62,054	(b)		8,970			37,720
Total Earnings	$	113,630	$	175,121	$	37,072		$	105,118	$	62,054		$	8,970		$	37,720
Ratio of Earnings to Fixed Charges		2.4		2.3		—	(c)		1.8		1.4			—	(c)		4.7
Rent/Lease Expense		32,796		21,483		20,351			20,600		18,700			5,131			4,821
Interest Capitalized		948		1,171		1,029			622		726			127			244

(a)

We estimated our interest factor for rentals to be 33.3 percent of our actual rental costs.

(b)

2003 earnings excluded addback for costs related to the early retirement of debt totaling $13.8 million.

(c)

For the year ended 2001 and for the quarter ended March 31, 2003, our earnings were insufficient to cover fixed charges by $28.0 million and $2.7 million, respectively.

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Ratio of Earnings to Fixed Charges Worksheet