EXHIBIT 11 BARRETT BUSINESS SERVICES, INC. STATEMENT OF CALCULATION OF AVERAGE COMMON SHARES OUTSTANDING Three Months Year Ended Ended Dec. 31, 1995 Dec. 31, 1995 ------------- ------------- Primary Earnings Per Share: Weighted average number of shares 6,490,411 6,474,055 Stock option plan shares to be issued at prices ranging from $3.50 to $16.363 per share 448,360 349,078 Warrant issues at a price of $4.20 per share 90,000 98,611 Less: Assumed purchase at average market price during the period using proceeds received upon exercise of options and purchase of stock, and using tax benefits of compensation due to premature dispositions (339,360) (242,137) --------- --------- Total Primary Shares 6,689,411 6,679,607 ========= ========= Fully Diluted Earnings Per Share: Weighted average number of shares 6,490,411 6,474,055 Stock option plan shares to be issued at prices ranging from $3.50 to $16.363 per share 448,360 349,078 Warrant issues at a price of $4.20 per share 90,000 98,611 Less: Assumed purchase at the higher of ending or average market price during the period using proceeds received upon exercise of options and purchase of stock, and using tax benefits of compensation due to premature dispositions (332,367) (232,254) --------- --------- Total Diluted Shares 6,696,404 6,689,490 ========= =========