Year Number 1970 83600 1971 96500 1972 110700 1973 120900 1974 126900 1975 137700 1976 141700 1977 149700 1978 150000 1979 167800 1980 171100 1981 158800 1982 161100 1983 169400 1984 177100 1985 190500 1986 229900 1987 233300 1988 222600 1989 221400 1990 233500 1991 228000 1992 253700 1993 249800 1994 259200 1995 266500 1996 279500 1997 301500 1998 305100 1999 334500 2000 320753 2001 306511 2002 270045 2003 248403 2004 254045