EXHIBIT 12.2 PUBLIC SERVICE COMPANY OF OKLAHOMA (CONSOLIDATED) RATIO OF EARNINGS TO FIXED CHARGES FOR THE TWELVE MONTHS ENDED MARCH 31, 1998 (Thousands Except Ratio) (Unaudited) Operating Income $79,901 Adjustments: Income taxes 13,331 Provision for deferred income taxes 6,299 Deferred investment tax credits (2,062) Other income and deductions 793 Allowance for borrowed and equity funds used during construction 2,237 --------- Earnings $100,499 ========= Fixed Charges: Interest on long-term debt $30,474 Interest on short-debt and other 3,718 Distributions on Trust Preferred Securities 5,467 --------- Fixed Charges $39,659 ========= Ratio of Earnings to Fixed Charges 2.53 =========