Year Number 1961 148245 1962 153000 1963 166532 1964 170000 1965 170000 1966 174067 1967 170000 1968 167000 1969 175000 1970 180000 1971 181519 1972 182000 1973 182514 1974 185200 1975 187000 1976 188800 1977 190000 1978 187000 1979 185000 1980 181000 1981 189654 1982 188500 1983 187300 1984 186200 1985 185000 1986 183828 1987 180000 1988 177000 1989 174000 1990 171000 1991 167328 1992 168900 1993 170000 1994 171500 1995 172470 1996 172500 1997 172400 1998 172300 1999 172000 2000 165000 2001 163900 2002 162800 2003 161700 2004 160600 2005 159590