EXHIBIT 12 NORTHWEST NATURAL GAS COMPANY Computation of Ratio of Earnings to Fixed Charges January 1, 1990 - September 30, 1995 ($000) Twelve Months Year Ended December 31 Ended ----------------------------------------- Sept.30, 1990 1991 1992 1993 1994 1995 ------- ------- ------- ------- ------- -------- Fixed Charges, as defined: Interest on Long- Term Debt $22,244 $21,977 $23,001 $22,578 $21,921 $23,103 Other Interest 2,853 4,266 3,223 1,906 2,473 2,447 Amortization of Debt Discount and Expense 363 348 511 775 850 888 Interest Portion of Rentals 1,546 1,485 1,439 1,701 1,697 1,697 ------- ------- ------- ------- ------- ------- Total Fixed Charges, as defined $27,006 $28,076 $28,174 $26,960 $26,941 $28,135 ======= ======= ======= ======= ======= ======= Earnings, as defined: Net Income $30,724 $14,377 $15,775 $37,647 $35,461 $36,202 Taxes on Income 13,629 2,321 6,951 22,096 20,473 22,352 Fixed Charges, as above 27,006 28,076 28,174 26,960 26,941 28,135 ------- ------- ------- ------- ------- ------- Total Earnings, as defined $71,359 $44,774 $50,900 $86,703 $82,875 $86,689 ======= ======= ======= ======= ======= ======= Ratio of Earnings to Fixed Charges 2.64 1.59 1.81 3.22 3.08 3.08 ==== ==== ==== ==== ==== ====