EXHIBIT 12 STATE STREET CORPORATION Ratio of Earnings to Fixed Charges - -------------------------------------------------------------------------------- Six Months Ended Year Ended December 31, June 30, ---------------------------------------- (Dollars in millions) 1999 1998 1997 1996 1995 1994 - -------------------------------------------------------------------------------- (A) Excluding interest on deposits: Earnings: Income before income taxes................... $ 376 $ 661 $ 568 453 $ 370 $343 Fixed charges............ 448 856 613 477 495 267 ------- ------- ------- ------- ------- ---- Earnings as adjusted.... $ 824 $ 1,517 $ 1,181 $ 930 $ 865 $610 ======= ======= ======= ======= ======= ==== Income before income taxes Pretax income from continuing operations as reported................ $ 373 $ 656 $ 564 $ 447 $ 366 $340 Share of pretax income (loss) of 50% owned subsidiaries not included in above....... 3 5 4 6 4 3 ------- ------- ------- ------- ------- ---- Net income as adjusted... $ 376 $ 661 $ 568 $ 453 $ 370 $343 ======= ======= ======= ======= ======= ==== Fixed charges: Interest on other borrowings.............. $ 408 $ 770 $ 548 $ 452 $ 482 $254 Interest on long-term debt including amortization of debt issue costs............. 35 66 55 15 9 9 Portion of rents representative of the interest factor in long term lease.............. 5 20 10 10 4 4 ------- ------- ------- ------- ------- ---- Fixed charges........... $ 448 $ 856 $ 613 $ 477 $ 495 $267 ======= ======= ======= ======= ======= ==== (B) Including interest on deposits: Adjusted earnings from (A) above............... $ 824 $ 1,517 $ 1,181 $ 930 $ 865 $610 Add interest on deposits................ 343 656 512 425 416 281 ------- ------- ------- ------- ------- ---- Earnings as adjusted.... $ 1,167 $ 2,173 $ 1,693 $ 1,355 $ 1,281 $891 ======= ======= ======= ======= ======= ==== Fixed charges: Fixed charges from (A) above................... $ 448 $ 856 $ 613 $ 477 $ 495 $267 Interest on deposits..... 343 656 512 425 416 281 ------- ------- ------- ------- ------- ---- Adjusted fixed charges.. $ 791 $ 1,512 $ 1,125 $ 902 $ 911 $548 ======= ======= ======= ======= ======= ==== Adjusted earnings to adjusted fixed charges.. 1.48x 1.44x 1.50x 1.50x 1.41x 1.63x - -------------------------------------------------------------------------------- Ratio of earnings to fixed charges........... 1.84x 1.77x 1.93x 1.95x 1.75x 2.29x