Exhibit 11.0 ARTHUR J. GALLAGHER & CO. COMPUTATION OF NET EARNINGS PER COMMON AND COMMON EQUIVALENT SHARE (UNAUDITED) THREE-MONTH PERIOD ENDED NINE-MONTH PERIOD ENDED SEPTEMBER 30, SEPTEMBER 30, 1996 1995 1996 1995 ------- ------- ------- ------- (IN THOUSANDS, EXCEPT PER SHARE DATA) Net earnings $18,057 $16,372 $34,534 $29,791 Adjustments to net earnings for computation 303 - 619 - ------- ------- ------- ------- Net earnings applicable to computation $18,360 $16,372 $35,153 $29,791 ======= ======= ======= ======= Average common shares outstanding 16,139 16,411 16,291 16,309 Dilutive effect of stock options 1,668 978 1,440 921 ------- ------- ------- ------- Weighted average number of common and common equivalent shares outstanding 17,807 17,389 17,731 17,230 ======= ======= ======= ======= Net earnings per common and common equivalent share $ 1.03 $ .94 $ 1.98 $ 1.73