EXHIBIT 11 SIS BANCORP, INC AND SUBSIDIARIES COMPUTATION OF PRO FORMA PRIMARY AND FULLY DILUTED EARNINGS PER SHARE (IN THOUSANDS EXCEPT PER SHARE AMOUNTS) TWELVE MONTHS ENDED DECEMBER 31, -------------------------- 1996 1995 1994 ------- ------- -------- PRIMARY: Net income (loss)................................. $18,160 $11,459 $(26,907) Pro forma income on net proceeds.................. -- -- 1,189 Pro forma ESOP adjustment......................... -- -- (1,028) Pro forma RSP adjustment.......................... -- -- (230) ------- ------- -------- Net income and pro forma net income (loss)........ $18,160 $11,459 $(26,976) ======= ======= ======== Weighted average and pro forma weighted shares outstanding during the period.................... 5,583 5,562 5,562 Unearned ESOP shares.............................. (336) (431) (431) Stock options considered outstanding during the period........................................... 139 25 25 Restricted stock shares considered outstanding during the period................................ 137 18 18 ------- ------- -------- Total shares...................................... 5,523 5,174 5,174 ======= ======= ======== Earnings per share and pro forma earnings (loss) per share........................................ $ 3.29 $ 2.21 $ (5.21) ======= ======= ======== FULLY DILUTED: Net income (loss)................................. $18,160 $11,459 $(26,907) Pro forma income on net proceeds.................. -- -- 1,189 Pro forma ESOP adjustment......................... -- -- (1,028) Pro forma RSP adjustment.......................... -- -- (230) ------- ------- -------- Net income and pro forma net income (loss)........ $18,160 $11,459 $(26,976) ======= ======= ======== Weighted average and pro forma weighted shares outstanding during the period.................... 5,583 5,562 5,562 Unearned ESOP shares.............................. (336) (431) (431) Stock options considered outstanding during the period........................................... 189 60 60 Restricted stock shares considered outstanding during the period................................ 137 30 30 ------- ------- -------- Total shares...................................... 5,573 5,221 5,221 ======= ======= ======== Net income and pro forma net income (loss) per share............................................ $ 3.26 $ 2.19 $ (5.17) ======= ======= ======== Net income per share for the year ended December 31, 1996 is computed on weighted average shares outstanding for the period. Pro forma net income (loss) per share for the years ended December 31, 1995 and 1994 assume that the stock issued in the conversion of the Bank from mutual to stock form had been issued as of the beginning of the year. This computation includes the impact of the Restricted Stock Plan ("RSP") and the Stock Option Plan which were approved by the stockholders at the Annual Meeting of the Stockholders held on May 31, 1995. For the year ended December 31, 1994 the fully diluted earnings per share calculation is anti-dilutive and therefore, the primary earnings per share is shown on Consolidated Statement of Operations in accordance with APB 15.