COMMUNITY BANK SYSTEM, INC. STATEMENT RE: EARNINGS PER SHARE COMPUTATION EXHIBIT 11 Three Months Ended Twelve Months Ended December 31, December 31, ---------------------------------------- -------------------------------------------- 1997 1996 1997 1996 Basic Earnings Per Share: Net Income $3,994,283 $3,677,991 $15,561,507 $14,133,044 Less: Accrued Dividends on Preferred Stock 0 (101,250) (78,750) (405,000) ---------------------------------------- -------------------------------------------- Income applicable to common stock $3,994,283 $3,576,741 $15,482,757 $13,728,044 ---------------------------------------- -------------------------------------------- Weighted average number of common shares 7,572,876 7,457,578 7,537,043 7,407,212 ---------------------------------------- -------------------------------------------- BASIC EARNINGS PER SHARE $ 0.53 $ 0.48 $ 2.05 $ 1.85 ======================================== ============================================ Diluted Earnings Per Share: Net Income $3,994,283 $3,677,991 $15,561,507 $14,133,044 Less: Accrued Dividends on Preferred Stock 0 (101,250) (78,750) (405,000) Income applicable ---------------------------------------- -------------------------------------------- to common stock $3,994,283 $3,576,741 $15,482,757 $13,728,044 ---------------------------------------- -------------------------------------------- Weighted average number of common shares 7,572,876 7,457,578 7,537,043 7,407,212 Add: Shares issuable from assumed exercise of incentive stock options 144,617 100,176 139,283 75,306 Weighted average number of ---------------------------------------- -------------------------------------------- common shares - adjusted 7,717,493 7,557,754 7,676,326 7,482,518 ---------------------------------------- -------------------------------------------- DILUTED EARNINGS PER SHARE $0.52 $0.47 $2.02 $1.83 ======================================== ============================================