EXHIBIT 12 CROWN CASTLE INTERNATIONAL CORP. COMPUTATION OF RATIO OF EARNINGS TO FIXED CHARGES (Dollars in thousands) Historical ------------------------------------------------- Years Ended Six Months Ended December 31, June 30, -------------------------- --------------------- 1995 1996 1997 1997 1998 ------- ------- ------- ------- -------- Computation of Earnings: Income (loss) before income taxes and minority interests........... $ (21) $ (947) $(11,893) $(2,123) $(12,823) Add: Fixed charges (as computed below)................................ 1,214 1,912 9,825 1,270 10,467 Equity in losses (earnings) of unconsolidated affiliate.......... -- -- 1,138 221 (525) ------- ------- ------- ------- -------- $ 1,193 $ 965 $ (930) $ (632) $ (2,881) ======= ======= ======= ======= ======== Computation of Fixed Charges: Interest expense................................................... $ 1,101 $ 1,748 $ 7,095 $ 1,129 $ 1,489 Amortization of deferred financing costs and discount on long- term debt........................................................ 36 55 2,159 67 8,538 Interest component of operating lease expense...................... 77 109 571 74 440 ------- ------- ------- ------- -------- $ 1,214 $ 1,912 $ 9,825 $ 1,270 $ 10,467 ======= ======= ======= ======= ======== Ratio of Earnings to Fixed Charges.................................. -- -- -- -- -- ======= ======= ======= ======= ======== Fixed Charge Coverage Deficiency.................................... $ 21 $ 947 $10,755 $ 1,902 $ 13,348 ======= ======= ======= ======= ======== Pro Forma --------------------------------- Year Ended Six Months December 31, Ended June 30, 1997 1998 ----------- --------- Computation of Earnings: Income (loss) before income taxes and minority interests........... $ (33,231) $ (20,404) Add: Fixed charges (as computed below)................................ 39,596 20,946 Equity in losses (earnings) of unconsolidated affiliate.......... -- -- ----------- --------- $ 6,365 542 ----------- --------- Computation of Fixed Charges: Interest expense................................................... $ 17,545 $ 11,328 Amortization of deferred financing costs and discount on long- term debt........................................................ 20,763 8,955 Interest component of operating lease expense...................... 1,288 663 ----------- --------- $ 39,596 $ 20,946 =========== ========= Ratio of Earnings to Fixed Charges.................................. -- -- =========== ========= Fixed Charge Coverage Deficiency.................................... $ 33,231 $ 20,404 =========== =========