Exhibit 11 AIRGAS, INC. AND SUBSIDIARIES EARNINGS PER SHARE CALCULATIONS For the Years Ended March 31, 2001, 2000 and 1999 Years Ended March 31, 2001 2000 1999 Weighted Average Shares Outstanding: - ------------------------------------ Basic shares outstanding 66,000,000 69,200,000 70,000,000 Net common stock equivalents 1,200,000 1,400,000 1,700,000 ---------- ---------- ---------- Diluted shares outstanding 67,200,000 70,600,000 71,700,000 ========== ========== ========== Net earnings $28,223,000 $38,283,000 $51,924,000 =========== =========== =========== Basic earnings per share $ .43 $ .55 $ .74 =========== =========== =========== Diluted earnings per share $ .42 $ .54 $ .72 =========== =========== ===========