Simpson Manufacturing Co., Inc. and Subsidiaries
Computation of Earnings Per Common Share
(Unaudited)

Exhibit 11

Basic Earnings per Share

		Three Months Ended								Nine Months Ended
		September 30,								September 30,
		2001				2000				2001				2000
Weighted average number of common shares outstanding			12,133,872				12,048,205				12,090,601				12,037,015
Net income		$	12,116,915			$	11,671,732			$	33,715,721			$	32,407,458
Basic net income per share		$	1.00			$	0.97			$	2.79			$	2.69

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Simpson Manufacturing Co., Inc. and Subsidiaries
Computation of Earnings Per Common Share
(Unaudited)

Exhibit 11 (continued)

Diluted Earnings per Share

		Three Months Ended								Nine Months Ended
		September 30,								September 30,
		2001				2000				2001				2000
Weighted average number of common shares outstanding			12,133,872				12,048,205				12,090,601				12,037,015
Shares issuable pursuant to employee stock option plans, less shares assumed repurchased at the average fair value during the period			212,684				282,350				215,021				269,985
Shares issuable pursuant to the independent director stock option plan, less shares assumed repurchased at the average fair value during the period			3,171				4,641				3,525				4,193
Number of shares for computation of diluted net income per share			12,349,727				12,335,196				12,309,147				12,311,193
Net income		$	12,116,915			$	11,671,732			$	33,715,721			$	32,407,458
Diluted net income per share		$	0.98			$	0.95			$	2.74			$	2.63

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