Exhibit No. 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,
	2006		2005		2004		2003		2002
	(dollars in millions)
Earnings as defined for fixed charges calculation
Add:
Pretax income	$	200	$	325	$	277	$	234	$	329
Fixed charges		145		126		103		97		89
Deduct:
Interest capitalized(a)		16		8		2		5		9
Total earnings (as defined for the Fixed Charges calculation)	$	329	$	443	$	378	$	326	$	409
Fixed charges:
Interest on debt, including capitalized portions	$	138	$	118	$	93	$	88	$	82
Estimate of interest within rental expense		7		8		10		9		7
Total fixed charges	$	145	$	126	$	103	$	97	$	89
Ratio of earnings to fixed charges		2.3		3.5		3.7		3.4		4.6

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