EXHIBIT 12 IDX SYSTEMS CORPORATION SCHEDULES OF NET INCOME PER SHARE AND PRO FORMA NET INCOME PER SHARE (IN THOUSANDS, EXCEPT FOR PER SHARE DATA) PRIMARY FULLY DILUTED SIX MONTHS ENDED JUNE 30, SIX MONTHS ENDED JUNE 30, 1996 1995 1996 1995 ------ ------ ------ ------ Weighted average shares outstanding 20,546 13,903 20,546 13,903 Net dilutive effect of stock options-based on the treasury stock method using the IPO price until the effective date and average price thereafter for primary and ending price, if higher, for fully diluted 805 1,471 805 1,555 Effect of final S corporation distribution 1,789 1,789 Effect of common and common stock equivalent shares issued by the Company during the twelve month period immediately preceding the Company's initial public offering in November 1995, as if they were outstanding for all periods presented prior to the initial public offering, using the treasury stock method, as described above 192 192 ------- ------- ------- ------- Total shares 21,351 17,355 21,351 17,439 ======= ======= ======= ======= Net income $ 7,209 $ 7,209 ======= ======= Net income per share $ 0.34 $ 0.34 ======= ======= Pro forma net income $ 4,783 $ 4,783 ======= ======= Pro forma net income per share $ 0.28 $ 0.28 ======= =======