EXHIBIT 11.1 STATEMENT RE: COMPUTATION OF PER SHARE EARNINGS Three Months Nine Months Ended September Ended September 30, 30, (in thousands) 1997 1998 1997 1998 Net income (basic) 4,844 10,613 11,431 22,687 Interest expense on 7% Convertible Notes net of tax effect 597 183 597 979 Net income (diluted) 5,441 10,796 12,028 23,666 Weighted average shares outstanding (basic) 14,189 19,198 16,070 17,737 Incremental shares related to stock 726 844 677 894 options Incremental shares related to 7% Convertible Notes 6,234 2,202 2,078 3,512 Weighted average shares outstanding 21,149 22,244 18,825 22,143 (diluted)