EXHIBIT 12

COMPUTATION OF RATIO OF EARNINGS TO FIXED CHARGES

The ratio of earnings to fixed charges is calculated using the Securities and Exchange Commission guidelines.

	Year Ended December 31,
	2008		2007		2006		2005		2004
	(dollars in millions)
Earnings as defined for fixed charges calculation
Add:
Pretax income	$	408	$	386	$	200	$	325	$	277
Fixed charges		140		130		145		126		103
Deduct:
Interest capitalized(a)		10		11		16		8		2
Total earnings (as defined for the Fixed Charges calculation)	$	538	$	505	$	329	$	443	$	378
Fixed charges:
Interest on debt, including capitalized portions	$	133	$	120	$	138	$	118	$	93
Estimate of interest within rental expense		7		10		7		8		10
Total fixed charges	$	140	$	130	$	145	$	126	$	103
Ratio of earnings to fixed charges		3.8		3.9		2.3		3.5		3.7

(a) Excludes equity costs related to AFUDC that are included in Other Income and Expenses in the Consolidated Statements of Operations.