| Year | Value | | 2021 | 4,338.726413195 | | 2020 | 3,386.1420496836 | | 2019 | 6,342.2662325425 | | 2018 | 6,707.3575666553 | | 2017 | 6,051.4897388441 | | 2016 | 5,064.1576272693 | | 2015 | 4,843.2549083729 | | 2014 | 5,139.320611477 | | 2013 | 4,914.1086791454 | | 2012 | 4,813.4230511985 | | 2011 | 4,815.0426357186 | | 2010 | 4,874.9997629939 | | 2009 | 3,540.243 | | 2008 | 3,739.776 | | 2007 | 3,560.205 | | 2006 | 3,754.011 | | 2005 | 3,603.044 | | 2004 | 3,400.943 | | 2003 | 2,965.055 | | 2002 | 2,809.799 | | 2001 | 3,034.232 | | 2000 | 3,108.404 | | 1999 | 2,896.3999934048 | | 1998 | 2,906.1999757664 | | 1997 | 3,248.5000233426 | | 1996 | 3,087.5000107063 | | 1995 | 3,097.300041415 | | 1994 | 2,871.2999968082 | | 1993 | 2,330.5999771282 | | 1992 | 2,374.1000039126 | | 1991 | 2,411.8000016139 | | 1990 | 2,655.2000385895 | | 1989 | 2,758.6999899298 | | 1988 | 2,713.1999993025 | | 1987 | 2,455.0000203327 | | 1986 | 2,047.200016782 | | 1985 | 2,151.5000064151 | | 1984 | 2,390.3000063003 | | 1983 | 2,285.5999874172 | | 1982 | 1,942.199995309 | | 1981 | 1,916.0999794825 | | 1980 | 1,771.8999700696 | | 1979 | 1,681.8000255451 | | 1978 | 1,570.7000166403 | | 1977 | 1,492.3000038863 | | 1976 | 1,412.7000103819 | | 1975 | 1,142.1999980065 | | 1974 | 920.6999862193 | | 1973 | 850.4000094906 | | 1972 | 629.0000127928 | | 1971 | 535.2000058967 | | 1970 | 447.5000086796 |
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