SOUTHWESTERN PUBLIC SERVICE COMPANY EXHIBIT 12. Statement of Computation of Ratio of Earnings Twelve Months Ended November 30, 1994 (Dollars In Thousands) Computation of Ratio of Earnings to Fixed Charges: Fixed charges, as defined: Interest on long-term debt $ 37,715 Amortization of debt premium, discount and expense 516 Other interest 3,337 Estimated interest factor of rental charges 1,184 Total fixed charges $ 42,752 Earnings as defined: Net earnings per statement of earnings $ 97,291 Fixed charges as shown 42,752 Income taxes: Federal-current 41,464 Federal-deferred 13,734 State 1,713 Investment tax credits (250) Earnings available for fixed charges $196,704 Ratio of earnings to fixed charges 4.60 Computation of Ratio of Earnings to Fixed Charges and Preferred Dividend Requirements Combined: Total fixed charges, as shown above $ 42,752 Preferred dividend requirements* 7,668 Total fixed charges and preferred dividend requirements combined $ 50,420 Earnings available for fixed charges and preferred dividend requirements combined $196,704 Ratio of earnings to fixed charges and preferred dividend requirements combined 3.90 *Preferred dividend requirements: Annual preferred dividend requirement $ 4,878 Less amount deductible for income tax purposes 84 Net requirement [A] $ 4,794 1 / (100% - effective tax rate) [B] 1.582 Effective tax rate 36.8% [A] x [B] $ 7,584 Add amount deductible for income tax purposes 84 Preferred dividend requirements $ 7,668