| Year | Value | | 2020 | 7,197.8019546246 | | 2019 | 7,621.5231265711 | | 2018 | 8,063.6011977865 | | 2017 | 8,921.2112197411 | | 2016 | 9,193.5742056656 | | 2015 | 9,294.2728117552 | | 2014 | 10,269.293408231 | | 2013 | 10,665.18720189 | | 2012 | 9,895.7287683168 | | 2011 | 9,534.7373444097 | | 2010 | 8,905.3166120118 | | 2009 | 7,429.9722239224 | | 2008 | 9,024.5958073786 | | 2007 | 8,093.6604017551 | | 2006 | 6,657.9005885583 | | 2005 | 6,114.8677079645 | | 2004 | 4,956.2476730159 | | 2003 | 3,818.689281049 | | 2002 | 2,911.222377877 | | 2001 | 2,471.5461723743 | | 2000 | 3,533.7429295236 | | 1999 | 3,343.6537863504 | | 1998 | 3,699.7375975365 | | 1997 | 2,572.1522811505 | | 1996 | 2,489.1703135178 | | 1995 | 2,351.0554815465 | | 1994 | 1,817.566637901 | | 1993 | 2,621.9535545598 | | 1992 | 2,330.5963577347 | | 1991 | 2,239.7318204244 | | 1990 | 2,300.1376205428 | | 1989 | 1,643.3437881274 | | 1988 | 1,394.8604485992 | | 1987 | 1,379.8773007456 | | 1986 | 1,245.6003145979 | | 1985 | 1,129.2896120864 | | 1984 | 1,027.4688950764 | | 1983 | 1,082.0595823447 | | 1982 | 1,160.8019261768 | | 1981 | 1,308.3428105127 | | 1980 | 1,297.8171917195 | | 1979 | 1,733.821720184 | | 1978 | 1,298.3673480476 | | 1977 | 1,197.9151642422 | | 1976 | 1,066.23300476 | | 1975 | 951.54933530138 | | 1974 | 770.87226265067 | | 1973 | 568.21477172401 | | 1972 | 459.43933077782 | | 1971 | 380.34316700258 | | 1970 | 407.17401364654 |
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