Exhibit 12(b) Aon Corporation and Consolidated Subsidiaries Combined With Unconsolidated Subsidiaries Computation of Ratio of Earnings to Combined Fixed Charges and Preferred Stock Dividends First Quarter Ended March 31, Years Ended December 31, ----------------- ------------------------------------------ (millions except ratios) 1999 1998 1998 1997 1996 1995 1994 -------- -------- ------- -------- ------- ------- -------- Income from continuing operations before provision for income taxes (1) $ 96 $ 238 $ 931 $ 542 $ 446 $ 458 $ 397 ADD BACK FIXED CHARGES: Interest on indebtedness 21 20 87 70 45 56 46 Interest on ESOP - 1 2 3 4 5 6 Portion of rents representative of interest factor 13 11 51 44 29 21 29 ------- ------- ------- ------- ------- ------- ------- INCOME AS ADJUSTED $ 130 $ 270 $ 1,071 $ 659 $ 524 $ 540 $ 478 ======= ======= ======= ======= ======= ======= ======= FIXED CHARGES AND PREFERRED STOCK DIVIDENDS: Interest on indebtedness $ 21 $ 20 $ 87 $ 70 $ 45 $ 56 $ 46 Preferred stock dividends 17 17 70 82 29 38 48 ------- ------- ------- ------- ------- ------- ------- Interest and dividends 38 37 157 152 74 94 94 Interest on ESOP - 1 2 3 4 5 6 Portion of rents representative of interest factor 13 11 51 44 29 21 29 TOTAL FIXED CHARGES AND PREFERRED ------- ------- ------- ------- ------- ------- ------- STOCK DIVIDENDS $ 51 $ 49 $ 210 $ 199 $ 107 $ 120 $ 129 ======= ======= ======= ======= ======= ======= ======= RATIO OF EARNINGS TO COMBINED FIXED CHARGES AND PREFERRED STOCK DIVIDENDS (2) 2.5 5.5 5.1 3.3 4.9 4.5 3.7 ======= ======= ======= ======= ======= ======= ======= RATIO OF EARNINGS TO COMBINED FIXED CHARGES AND PREFERRED STOCK DIVIDENDS (3) 5.7 4.2 5.8 ======= ======= ======= <FN> (1) Income from continuing operations before provision for income taxes and minority interest includes special charges of $163 million for the first quarter ended March 31, 1999 and $172 million and $90 million for the years ended December 31, 1997 and 1996, respectively. (2) Included in total fixed charges and preferred stock dividends are $16 million for the first quarters ended March 31, 1999 and 1998, and $66 million and $64 million for the years ended December 31, 1998 and 1997, respectively, of pretax distributions on the 8.205% mandatorily redeemable preferred capital securities which are classified as "minority interest" on the condensed consolidated statements of operations. (3) The calculation of this ratio of earnings to fixed charges reflects the exclusion of special charges from the income from continuing operations before provision for income taxes component for the first quarter ended March 31, 1999 and for the years ended December 31, 1997 and 1996, respectively. </FN>