EXHIBIT 12 NORTHWEST NATURAL GAS COMPANY Computation of Ratio of Earnings to Fixed Charges January 1, 1995 - June 30, 2000 (Thousands, except ratio amounts) (Unaudited) Twelve Six Months Months Year Ended Dec. 31, Ended Ended ----------------------------------------------------- June 30, June 30, 1995 1996 1997 1998 1999 2000 2000* --------- --------- --------- --------- --------- --------- --------- Fixed Charges, as Defined: Interest on Long-Term Debt $ 23,141 $ 23,176 $ 24,904 $ 27,389 $ 27,728 $ 28,914 $ 14,920 Other Interest 2,252 3,448 4,500 4,909 2,778 3,380 1,470 Amortization of Debt Discount and Expense 882 865 730 714 699 707 362 Interest Portion of Rentals 1,764 1,798 2,111 1,986 1,707 1,707 814 --------- --------- --------- --------- --------- --------- --------- Total Fixed Charges, as defined $ 28,039 $ 29,287 $ 32,245 $ 34,998 $ 32,912 $ 34,708 $ 17,566 ========= ========= ========= ========= ========= ========= ========= Earnings, as defined: Net Income $ 38,065 $ 46,793 $ 43,059 $ 27,301 $ 45,296 $ 44,594 $ 34,125 Taxes on Income 22,120 27,347 21,034 14,604 24,591 22,077 17,717 Fixed Charges, as above 28,039 29,287 32,245 34,998 32,912 34,708 17,566 --------- --------- --------- --------- --------- --------- --------- Total Earnings, as defined $ 88,224 $ 103,427 $ 96,338 $ 76,903 $ 102,799 $ 101,379 $ 69,408 ========= ========= ========= ========= ========= ========= ========= Ratio of Earnings to Fixed Charges 3.15 3.53 2.99 2.20 3.12 2.92 3.95 ========= ========= ========= ========= ========= ========= ========= * A significant part of the business of the Company is of a seasonal nature; therefore, the ratio of earnings to fixed charges for the interim period is not necessarily indicative of the results for a full year.