EXHIBIT 11

NORTHWEST NATURAL GAS COMPANY

Statement re: Computation of Per Share Earnings

(Unaudited)

	Three Months Ended March 31,
Thousands, except per share amounts	2005		2004
Net income	$	39,887	$	32,612
Debenture interest less taxes		48		62
Net income - diluted	$	39,935	$	32,674
Average common shares outstanding - basic		27,578		25,972
Stock options		65		59
Convertible debentures		220		283
Average common shares outstanding - diluted		27,863		26,314
Earnings per share of common stock - basic	$	1.45	$	1.26
Earnings per share of common stock - diluted	$	1.43	$	1.24

For the three months ended March 31, 2005 and 2004, no shares were excluded from the calculation of diluted earnings per share because the effect would have been antidilutive.