EXHIBIT 11 BANK OF BOSTON CORPORATION Computation of Earnings Per Common Share (in thousands, except per share amounts) Quarters Ended -------------- March 31 EARNINGS 1994 1993 - -------- ---- ---- 1. Net income $ 96,140 $ 83,675 2. Less: Preferred dividends 9,317 7,938 ------- ------- 3. Net income applicable to primary earnings per common share 86,823 75,737 4. Add: Interest expense on convertible debentures, net of tax 1,061 1,078 ------- ------- 5. Net income applicable to fully diluted earnings per common share $ 87,884 $ 76,815 ======= ======= SHARES ------ 6. Weighted average number of common shares outstanding 106,198 104,962 7. Incremental shares from assumed exercise of dilutive stock options as of the beginning of the period using the treasury stock method 589 1,075 8. Incremental shares from assumed conversion of debentures at date of issuance 4,030 4,042 ------- ------- 9. Adjusted number of common shares 110,817 110,079 ======= ======= PER SHARE CALCULATION --------------------- 10. Primary net income per common share $ .82 $ .72 (Item 3 / Item 6); see note below 11. Fully diluted net income per common share $ .79 $ .70 (Item 5 / Item 9); see note below <FN> Note - Income per common share before extraordinary items and cumulative effect of accounting changes, net, on both a primary and fully diluted basis for the quarters ended March 31, 1994 and March 31, 1993 are computed by adding to the numerator $6,535 and subtracting from the numerator $24,203, respectively.