EXHIBIT 11 TRI-COUNTY BANCORP, INC. AND SUBSIDIARIES STATEMENT REGARDING COMPUTATION OF EARNINGS PER SHARE Six Months Ended June 30, 1999 1998 -------- -------- EARNINGS PER SHARE Net earnings available for common shares and common stock equivalent shares deemed to have a dilutive effect $360,604 $458,988 ======== ======== Basic earnings per share $0.43 $0.39 ===== ===== Diluted earnings per share $0.40 $0.36 ===== ===== Shares used in basic earnings per share computation Weighted average common shares outstanding 879,536 1,167,498 ======= ========= Shares used in diluted earnings per share computation Weighted average common shares outstanding 947,578 1,260,520 Additional potentially dilutive effect of stock option 68,042 93,022 ------ ------ 879,536 1,167,498 ======= ========= -19-