Year Number 1961 792.0248667850799 1962 879.1671624033313 1963 987.312801932367 1964 1073.6511768255884 1965 1155.0060240963855 1966 1275.7116336633662 1967 1361.64375 1968 1432.2860712054967 1969 1510.9526813880127 1970 1569.8612862547288 1971 1630.0189035916824 1972 1690.5100755667504 1973 1833.7582562747689 1974 1878.560105680317 1975 1919.2587690271341 1976 1934.2105263157894 1977 2012.0143884892086 1978 2023.2708468002584 1979 2087.3276428102427 1980 2083.984375 1981 2080.6972240154937 1982 2124.1693811074915 1983 2265.879082696317 1984 2256.470588235294 1985 2251.795580110497 1986 2265.879082696317 1987 2265.879082696317 1988 2410.4526748971193 1989 2408.8005483207676 1990 2373.646563814867 1991 2352.9411764705883 1992 2374.651810584958 1993 2415.898520084567 1994 2424.455375966268 1995 2517.807637906648 1996 2517.7304964539007 1997 2506.2233285917496 1998 2450.1424501424503 1999 2394.636233951498 2000 2394.7676912080055 2001 2410.4397981254506 2002 2408.8664259927796 2003 2412.4692941457797 2004 2408.671065032988 2005 2401.15883247628