Exhibit 11 MAHASKA INVESTMENT COMPANY AND SUBSIDIARIES STATEMENT RE: COMPUTATION OF PER SHARE EARNINGS Three Months Ended March 31, ------------------------ 2003 2002 ----------- ---------- Earnings per Share Information: - --------------------------------------- Weighted average number of shares outstanding during the year .......................... 3,914,174 3,871,038 Weighted average number of shares outstanding during the year including all dilutive potential shares .............. 4,014,405 3,937,121 Net earnings .......................................... $ 1,339,128 $1,487,356 Earnings per share - basic ............................ $ 0.34 $ 0.38 Earnings per share - diluted .......................... $ 0.33 $ 0.38