Exhibit 11 STATE STREET BOSTON CORPORATION COMPUTATION OF EARNINGS PER SHARE (Dollars in thousands, Three Months Ended except per share data) March 31, ------------------ 1995 1994 ---------- ---------- Primary Average shares outstanding 82,499,807 82,020,578 Common stock equivalents 390,605 628,826 ---------- ---------- Primary shares outstanding 82,890,412 82,649,404 ========== ========== Net income $54,336 $54,197 ======= ======= Earnings Per Share-primary $ .66 $ .66 ======= ======= Fully Diluted Average shares outstanding 82,499,807 82,020,578 Common stock equivalents 406,731 628,826 Assumed conversion of 7 3/4% convertible subordinated debentures 581,391 697,022 -------- ---------- Fully diluted average shares outstanding 83,487,929 83,346,426 ========== ========== Net income $54,336 $54,197 Elimination of interest on 7 3/4% convertible subordinated debentures and 5% convertible notes less related income tax effect 37 43 ------- ------- Fully diluted net income $54,373 $54,240 ======= ======= Earnings Per Share-fully diluted $ .65 $ .65 ======= =======