EXHIBIT 12.2 Public Service Company of Oklahoma Consolidated Ratio of Earnings to Fixed Charges For Years Ended December 31, 1996 1995 1994 1993(2) 1992 --------- --------- --------- -------- -------- (thousands, except ratios) Operating income $101,737 $111,769 $98,258 $72,156 $78,096 Adjustments: Income taxes 25,257 37,490 27,954 13,554 (835) Provision for deferred income taxes (1,328) 2,704 7,779 9,537 21,157 Deferred investment tax credits (2,784) (2,789) (2,789) (2,838) (2,711) Reserve for utility plant costs, net of tax (35,708) -- -- -- -- Other income and deductions (95) 2,274 933 531 (940) Allowance for borrowed and equity funds used during construction 1,722 3,734 2,513 1,948 740 Interest portion of financing leases -- -- -- 17 37 ========= ========= ========= ======== ======== Earnings $88,801 $155,182 $134,648 $94,905 $95,544 ========= ========= ========= ======== ======== Fixed charges: Interest on long-term debt $30,555 $29,594 $29,594 $31,410 $30,688 Interest on short-term debt and other 5,623 6,355 3,844 2,729 1,646 Interest portion of financing leases -- -- -- 17 37 ========= ========= ========= ======== ======== Fixed charges $36,178 $35,949 $33,438 $34,156 $32,371 ========= ========= ========= ======== ======== Ratio of earnings to fixed charges 2.45 (1) 4.32 4.03 2.78 (3) 2.95 (1) Earnings in 1996 reflect a $35.7 million one-time charge, net of tax, associated with certain investments for plant sites, engineering studies and lignite reserves. (2) Earnings in 1993 were significantly affected by restructuring charges, the $6 million cumulative effect of changes in accounting principles and the establishment of reserves for fuel and other properties. (3) The ratio of earnings to fixed charges for 1993 was calculated before cumulative effect of changes in accounting principles.