| Year | Value | | 2021 | 5,094.6255538312 | | 2020 | 4,578.5988755823 | | 2019 | 5,361.5165271944 | | 2018 | 5,601.7353639454 | | 2017 | 5,421.7589260531 | | 2016 | 5,050.7890186469 | | 2015 | 5,244.145101029 | | 2014 | 6,572.1811597492 | | 2013 | 6,536.1847604826 | | 2012 | 6,324.5019212205 | | 2011 | 5,695.1369378088 | | 2010 | 5,117.4553795387 | | 2009 | 4,276.8876996394 | | 2008 | 4,371.3426124913 | | 2007 | 3,847.3298440298 | | 2006 | 3,032.7928542575 | | 2005 | 2,791.1846946795 | | 2004 | 2,257.0088312739 | | 2003 | 1,865.208572348 | | 2002 | 1,986.540193649 | | 2001 | 2,029.4389088887 | | 2000 | 2,057.2732444265 | | 1999 | 1,833.4829699959 | | 1998 | 2,202.3729134953 | | 1997 | 2,412.6092990057 | | 1996 | 2,233.9538544575 | | 1995 | 2,205.0614510284 | | 1994 | 2,003.218542537 | | 1993 | 1,638.9723011843 | | 1992 | 1,443.7795017426 | | 1991 | 1,219.5420343461 | | 1990 | 1,171.8335414791 | | 1989 | 986.04175067813 | | 1988 | 1,037.1813531519 | | 1987 | 958.97660508122 | | 1986 | 968.46266291951 | | 1985 | 979.18052959581 | | 1984 | 1,112.3883708246 | | 1983 | 1,167.9514964748 | | 1982 | 1,228.6944669386 | | 1981 | 1,182.5958767428 | | 1980 | 1,116.0849600465 | | 1979 | 952.191198704 | | 1978 | 817.64767031486 | | 1977 | 691.29978513441 | | 1976 | 543.36221764974 | | 1975 | 468.07996186684 | | 1974 | 451.59535231086 | | 1973 | 390.62966391905 | | 1972 | 331.91985215075 | | 1971 | 304.80321906402 | | 1970 | 285.99078505899 |
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