| Year | Value | | 2022 | 321,788 | | 2021 | 313,424 | | 2020 | 307,349 | | 2019 | 303,844 | | 2018 | 296,956 | | 2017 | 289,372 | | 2016 | 283,078 | | 2015 | 275,766 | | 2014 | 270,338 | | 2013 | 268,763 | | 2012 | 269,780 | | 2011 | 273,660 | | 2010 | 277,890 | | 2009 | 278,960 | | 2008 | 278,630 | | 2007 | 279,023 | | 2006 | 277,549 | | 2005 | 274,237 | | 2004 | 270,476 | | 2003 | 266,318 | | 2002 | 261,099 | | 2001 | 256,402 | | 2000 | 252,816 | | 1999 | 249,989 | | 1998 | 247,545 | | 1997 | 244,018 | | 1996 | 239,228 | | 1995 | 234,325 | | 1994 | 227,565 | | 1993 | 216,957 | | 1992 | 207,390 | | 1991 | 200,212 | | 1990 | 193,271 | | 1989 | 190,419 | | 1988 | 193,842 | | 1987 | 197,924 | | 1986 | 200,521 | | 1985 | 202,853 | | 1984 | 203,045 | | 1983 | 200,678 | | 1982 | 197,796 | | 1981 | 193,789 | | 1980 | 187,078 | | 1979 | 181,004 | | 1978 | 177,527 | | 1977 | 174,030 | | 1976 | 169,248 | | 1975 | 163,492 | | 1974 | 154,621 | | 1973 | 146,986 | | 1972 | 142,233 | | 1971 | 139,625 | | 1970 | 132,779 | | 1969 | 127,820 | | 1968 | 129,362 | | 1967 | 129,558 | | 1966 | 129,187 | | 1965 | 129,736 | | 1964 | 129,519 | | 1963 | 127,230 | | 1962 | 124,805 | | 1961 | 122,576 | | 1960 | 119,290 |
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