Numbers were derived from the dates of operation as reported by InCoasterPaedia or the Roller Coaster Database. Flying Turns rides and kiddie coasters are included. Virginia Reels and wooden Wild Mouse rides are excluded, due to lack of reliable data. Their inclusion would increase the decline from 1960 to 1990 by at least a dozen.
Most coaster losses were due to park closings. Although 60 new coasters were built between 1960 and 1990, a far greater number were lost during that period. In contrast, very few coasters closed permanently between 1990 and 2000. From 2000 to 2007, additions and losses were nearly equal.