EXHIBIT (12) NORTHWEST NATURAL GAS COMPANY Computation of Ratio of Earnings to Fixed Charges January 1, 1995 - December 31, 1999 ($000) Year Ended December 31 ----------------------------------------------------------- 1995 1996 1997 1998 1999 ---- ---- ---- ---- ---- Fixed Charges, as defined: Interest on Long-Term Debt $23,141 $23,176 $24,904 $27,389 $27,728 Other Interest 2,252 3,448 4,500 4,909 2,778 Amortization of Debt Discount and Expense 882 865 730 714 699 Interest Portion of Rentals 1,764 1,798 2,111 1,986 1,707 -------- --------- -------- -------- ----- Total Fixed Charges, as defined $28,039 $29,287 $32,245 $34,998 $32,912 ======== ========= ======== ======== ========= Earnings, as defined: Net Income $38,065 $46,793 $43,059 $27,301 $45,296 Taxes on Income 22,120 27,347 21,034 14,604 24,591 Fixed Charges, as above 28,039 29,287 32,245 34,998 32,912 -------- --------- -------- -------- --------- Total Earnings, as defined $88,224 $103,427 $96,338 $76,903 $102,799 ======== ========= ======== ======== ========= Ratio of Earnings to Fixed Charges 3.15 3.53 2.99 2.20 3.12 ======== ========= ======== ======== =========