EXHIBIT 11 NORTHWEST NATURAL GAS COMPANY Statement Re: Computation of Per Share Earnings (Thousands, except per share amounts) (Unaudited) Three Months Ended March 31, ------------------ 1994 1993 ------- ------- Earnings Applicable to Common Stock. . . . $18,040 $23,697 Preference Stock Dividends . . . . . . . . . . 39 41 Debenture Interest Less Taxes. . . . . . . . . 136 149 ------- ------- Net Income Available for Fully-Diluted Common Stock. . . . . . . . . . . . . . . . . $18,215 $23,887 ======= ======= Average Common Shares Outstanding. . . . . . . . 13,209 12,997 Stock Options. . . . . . . . . . . . . . . . . 23 26 Convertible Preference Stock . . . . . . . . . 107 113 Convertible Debentures . . . . . . . . . . . 413 446 ------- ------- Fully-Diluted Common Shares. . . . . . . . . . .13,752 13,582 ======= ======= Fully-Diluted Earnings Per Share of Common Stock . . . . . . . . . . . . . . . . . . . . . $1.32 $1.76 ======= ======= Note: Primary earnings per share are computed on the weighted daily average number of common shares outstanding each period. Outstanding stock options are common stock equivalents but are excluded from primary earnings per share computations due to immateriality.