EXHIBIT 12 RATIO OF EARNINGS TO FIXED CHARGES: COMPUTATION OF HISTORICAL RATIOS: 1993 1994 1995 1996 1997 1998 1999 - ---------------------------------------- -------- -------- -------- -------- -------- -------- -------- Earnings-- Income before income taxes............ 19,664 27,401 18,920 30,193 18,194 37,494 60,544 Fixed charges......................... 6,776 11,657 15,472 15,516 17,078 22,740 28,807 Less: interest capitalized............ (6,553) (11,306) (14,737) (14,176) (16,159) (21,259) (26,874) Add: interest amortized to COS........ 3,049 9,768 13,268 15,134 14,857 19,031 25,469 ------ ------- ------- ------- ------- ------- ------- Earnings available for fixed charges............................. 22,936 37,520 32,923 46,667 33,970 58,006 87,946 ------ ------- ------- ------- ------- ------- ------- Fixed charges-- Interest incurred and capitalized..... 6,553 11,306 14,737 14,176 16,159 21,259 26,874 Interest expense...................... -- -- -- -- -- -- -- Portion of rents representative....... 223 351 735 1,340 919 1,481 1,933 ------ ------- ------- ------- ------- ------- ------- Total fixed charges................... 6,776 11,657 15,472 15,516 17,078 22,740 28,807 ------ ------- ------- ------- ------- ------- ------- Ratio of earnings to fixed charges...... 3.38 3.22 2.13 3.01 1.99 2.55 3.05 ====== ======= ======= ======= ======= ======= ======= RATIO OF EARNINGS TO FIXED CHARGES AND PREFERRED PAYMENT ITEMS: COMPUTATION OF HISTORICAL RATIOS: 1993 1994 1995 1996 1997 1998 1998 - ------------------------------------------------ -------- -------- -------- -------- -------- -------- -------- Earnings-- Income before income taxes................ 19,664 27,401 18,920 30,193 18,194 37,494 60,544 Fixed charges............................. 6,776 11,657 16,083 19,516 21,078 26,740 32,150 Less: interest capitalized................ (6,553) (11,306) (14,737) (14,176) (16,159) (21,259) (26,874) Add: interest amortized to COS............ 3,049 9,768 13,268 15,134 14,857 19,031 25,469 ------ ------- ------- ------- ------- ------- ------- Earnings available for fixed charges...... 22,936 37,520 33,534 50,667 37,970 62,006 91,289 ------ ------- ------- ------- ------- ------- ------- Fixed charges-- Interest incurred and capitalized......... 6,553 11,306 14,737 14,176 16,159 21,259 26,874 Interest expense.......................... -- -- -- -- -- -- -- Preferred dividend requirements........... -- -- 611 4,000 4,000 4,000 3,343 Portion of rents representative........... 223 351 735 1,340 919 1,481 1,933 ------ ------- ------- ------- ------- ------- ------- Total fixed charges....................... 6,776 11,657 16,083 19,516 21,078 26,740 32,150 ------ ------- ------- ------- ------- ------- ------- Ratio of earnings to fixed charges.......... 3.38 3.22 2.09 2.60 1.80 2.32 2.84 ====== ======= ======= ======= ======= ======= ======= 2