COMMUNITY BANK SYSTEM, INC. Statement re: Earnings Per Share Computation Exhibit 11 Three Months Ended Nine Months Ended September 30, September 30, 1997 1996 1997 1996 Primary Earnings Per Share: Net Income $4,234,649 $3,792,234 $11,567,224 $10,455,053 Less: Accrued Dividends on Preferred Stock 0 (101,250) (78,750) (303,750) Income applicable ---------------------------- ----------------------------- to common stock $4,234,649 $3,690,984 $11,488,474 $10,151,303 ---------------------------- ----------------------------- Weighted average number of common shares 7,544,738 7,375,762 7,524,963 7,390,294 Add: Shares issuable from assumed exercise of incentive stock options 152,457 73,084 135,709 65,564 Weighted average number of ---------------------------- ----------------------------- common shares - adjusted 7,697,195 7,448,846 7,660,672 7,455,858 ---------------------------- ----------------------------- Primary Earnings Per Share $0.55 $0.50 $1.50 $1.36 ============================ ============================= Fully diluted Earnings Per Share: Net income applicable to common stock $4,234,649 $3,690,984 $11,488,474 $10,151,303 ---------------------------- ----------------------------- Weighted average number of common shares - adjusted 7,703,538 7,459,752 7,693,682 7,472,018 Add: Equivalent number of common shares assuming conversion of preferred 0 0 0 0 Weighted average number of ---------------------------- ----------------------------- common shares - adjusted 7,703,538 7,459,752 7,693,682 7,472,018 ---------------------------- ----------------------------- Fully diluted earnings per share $0.55 $0.49 $1.49 $1.36 ============================ =============================