| Year | Value | | 2018 | 357,429 | | 2017 | 350,776 | | 2016 | 344,098 | | 2015 | 337,410 | | 2014 | 330,707 | | 2013 | 324,023 | | 2012 | 317,394 | | 2011 | 310,897 | | 2010 | 304,564 | | 2009 | 296,947 | | 2008 | 289,438 | | 2007 | 282,010 | | 2006 | 274,601 | | 2005 | 267,119 | | 2004 | 259,568 | | 2003 | 251,947 | | 2002 | 244,270 | | 2001 | 236,551 | | 2000 | 228,802 | | 1999 | 220,758 | | 1998 | 212,742 | | 1997 | 204,705 | | 1996 | 196,596 | | 1995 | 188,383 | | 1994 | 180,051 | | 1993 | 171,686 | | 1992 | 163,552 | | 1991 | 155,956 | | 1990 | 149,104 | | 1989 | 137,453 | | 1988 | 126,722 | | 1987 | 116,749 | | 1986 | 107,285 | | 1985 | 98,179 | | 1984 | 91,204 | | 1983 | 84,464 | | 1982 | 78,080 | | 1981 | 72,155 | | 1980 | 66,755 | | 1979 | 64,394 | | 1978 | 62,448 | | 1977 | 60,705 | | 1976 | 59,185 | | 1975 | 57,884 | | 1974 | 56,832 | | 1973 | 55,973 | | 1972 | 55,108 | | 1971 | 53,990 | | 1970 | 52,541 | | 1969 | 50,728 | | 1968 | 48,556 | | 1967 | 46,181 | | 1966 | 43,824 | | 1965 | 41,643 | | 1964 | 39,656 | | 1963 | 37,823 | | 1962 | 36,195 | | 1961 | 34,799 | | 1960 | 33,652 |
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