| Year | Value | | 2021 | 3,905.9067528065 | | 2020 | 3,833.6140115204 | | 2019 | 3,973.9915394809 | | 2018 | 3,893.3638348986 | | 2017 | 3,810.7976189606 | | 2016 | 3,668.0504769983 | | 2015 | 3,736.5022811078 | | 2014 | 3,917.0959734295 | | 2013 | 4,127.9379261767 | | 2012 | 4,011.215959876 | | 2011 | 3,791.6663862846 | | 2010 | 3,588.6299267384 | | 2009 | 3,380.2904438571 | | 2008 | 3,205.2377982543 | | 2007 | 2,542.5482194304 | | 2006 | 2,381.843808592 | | 2005 | 2,108.6238071175 | | 2004 | 1,965.8564236815 | | 2003 | 1,777.7709331079 | | 2002 | 1,687.963498401 | | 2001 | 1,630.1705787368 | | 2000 | 1,558.7185030604 | | 1999 | 1,471.658396512 | | 1998 | 1,467.6444917831 | | 1997 | 1,361.4838135854 | | 1996 | 1,325.7926227729 | | 1995 | 1,340.3387767173 | | 1994 | 1,283.3841166349 | | 1993 | 1,205.7802853466 | | 1992 | 1,188.292770393 | | 1991 | 984.13031345768 | | 1990 | 1,048.2250398242 | | 1989 | 1,117.9197985054 | | 1988 | 1,742.6917310008 | | 1987 | 2,010.2805529776 | | 1986 | 2,025.7478901234 | | 1985 | 1,652.7779418106 | | 1984 | 1,758.8311359485 | | 1983 | 1,870.5304204256 | | 1982 | 1,873.9068571827 | | 1981 | 1,848.8254108505 | | 1980 | 1,705.4825120226 | | 1979 | 1,493.1236409007 | | 1978 | 1,226.8911253697 | | 1977 | 1,019.2884959441 | | 1976 | 852.19684275926 | | 1975 | 714.48777279101 | | 1974 | 643.2804086894 | | 1973 | 524.94146540709 | | 1972 | 451.26445647211 | | 1971 | 405.10628213432 |
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