Exhibit 11.0 ARTHUR J. GALLAGHER & CO. COMPUTATION OF NET EARNINGS PER COMMON AND COMMON EQUIVALENT SHARE (UNAUDITED) Three-month period ended March 31, 1997 1996 -------- -------- (In thousands, except per share data) Net earnings $ 9,238 $ 8,534 Adjustments to net earnings for computation related to the 20% limitation on the buyback of common shares using the treasury stock method 331 122 ------- ------- Net earnings applicable to computation $ 9,569 $ 8,656 ======= ======= Average common shares outstanding 16,484 16,578 Dilutive effect of stock options using the treasury stock method 1,614 1,338 ------- ------- Weighted average number of common and common equivalent shares outstanding 18,098 17,916 ======= ======= Net earnings per common and common equivalent share $ .53 $ .48