| Year | Value | | 2022 | 20,160 | | 2021 | 19,174 | | 2020 | 18,213 | | 2019 | 17,310 | | 2018 | 16,482 | | 2017 | 15,748 | | 2016 | 15,146 | | 2015 | 14,685 | | 2014 | 14,335 | | 2013 | 14,072 | | 2012 | 13,891 | | 2011 | 13,770 | | 2010 | 13,667 | | 2009 | 13,504 | | 2008 | 13,236 | | 2007 | 12,862 | | 2006 | 12,355 | | 2005 | 11,689 | | 2004 | 10,882 | | 2003 | 10,008 | | 2002 | 9,128 | | 2001 | 8,284 | | 2000 | 7,499 | | 1999 | 6,830 | | 1998 | 6,245 | | 1997 | 5,673 | | 1996 | 5,129 | | 1995 | 4,625 | | 1994 | 4,170 | | 1993 | 3,775 | | 1992 | 3,450 | | 1991 | 3,210 | | 1990 | 3,077 | | 1989 | 3,020 | | 1988 | 3,011 | | 1987 | 3,052 | | 1986 | 3,129 | | 1985 | 3,229 | | 1984 | 3,343 | | 1983 | 3,465 | | 1982 | 3,593 | | 1981 | 3,721 | | 1980 | 3,884 | | 1979 | 4,104 | | 1978 | 4,326 | | 1977 | 4,521 | | 1976 | 4,695 | | 1975 | 4,839 | | 1974 | 4,971 | | 1973 | 5,096 | | 1972 | 5,201 | | 1971 | 5,266 | | 1970 | 5,243 | | 1969 | 5,128 | | 1968 | 4,973 | | 1967 | 4,821 | | 1966 | 4,677 | | 1965 | 4,548 | | 1964 | 4,440 | | 1963 | 4,349 | | 1962 | 4,274 | | 1961 | 4,239 | | 1960 | 4,230 |
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