| Year | Value | | 2022 | 28,092 | | 2021 | 29,305 | | 2020 | 29,828 | | 2019 | 29,939 | | 2018 | 29,437 | | 2017 | 28,010 | | 2016 | 27,017 | | 2015 | 26,676 | | 2014 | 25,755 | | 2013 | 25,001 | | 2012 | 24,377 | | 2011 | 23,471 | | 2010 | 22,439 | | 2009 | 21,511 | | 2008 | 20,651 | | 2007 | 19,831 | | 2006 | 19,066 | | 2005 | 18,361 | | 2004 | 17,701 | | 2003 | 17,079 | | 2002 | 16,481 | | 2001 | 15,845 | | 2000 | 15,136 | | 1999 | 14,344 | | 1998 | 13,465 | | 1997 | 12,534 | | 1996 | 11,629 | | 1995 | 10,823 | | 1994 | 10,121 | | 1993 | 9,521 | | 1992 | 9,026 | | 1991 | 8,615 | | 1990 | 8,265 | | 1989 | 7,984 | | 1988 | 7,783 | | 1987 | 7,643 | | 1986 | 7,521 | | 1985 | 7,383 | | 1984 | 7,223 | | 1983 | 7,022 | | 1982 | 6,789 | | 1981 | 6,587 | | 1980 | 6,465 | | 1979 | 6,417 | | 1978 | 6,446 | | 1977 | 6,537 | | 1976 | 6,627 | | 1975 | 6,684 | | 1974 | 6,719 | | 1973 | 6,733 | | 1972 | 6,723 | | 1971 | 6,694 | | 1970 | 6,652 | | 1969 | 6,587 | | 1968 | 6,502 | | 1967 | 6,412 | | 1966 | 6,333 | | 1965 | 6,278 | | 1964 | 6,248 | | 1963 | 6,228 | | 1962 | 6,211 | | 1961 | 6,203 | | 1960 | 6,213 |
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