| Year | Value | | 2014 | 4,797.6704359594 | | 2013 | 4,934.2746811249 | | 2012 | 5,062.8583451686 | | 2011 | 7,379.1196769895 | | 2010 | 7,471.2682326517 | | 2009 | 7,423.3993720758 | | 2008 | 7,149.7120921305 | | 2007 | 7,323.5408452269 | | 2006 | 7,243.0419360092 | | 2005 | 7,613.0700722079 | | 2004 | 7,571.2412066293 | | 2003 | 7,521.0201899967 | | 2002 | 7,282.9998839054 | | 2001 | 7,222.1748665215 | | 2000 | 7,291.1997609443 | | 1999 | 7,000.0286886422 | | 1998 | 6,769.4778226923 | | 1997 | 6,280.7915294374 | | 1996 | 6,301.8604841907 | | 1995 | 6,090.7130406025 | | 1994 | 5,883.9798105511 | | 1993 | 5,537.1139093133 | | 1992 | 5,162.8773139141 | | 1991 | 4,771.3690158792 | | 1990 | 4,662.9986244842 | | 1989 | 4,253.5236189659 | | 1988 | 3,939.5929087328 | | 1987 | 3,829.4950348616 | | 1986 | 3,438.969750167 | | 1985 | 4,230.212623845 | | 1984 | 4,574.174016059 | | 1983 | 4,961.662884777 | | 1982 | 4,950.000333109 | | 1981 | 4,857.7330130728 | | 1980 | 4,877.027310002 | | 1979 | 4,815.6590080554 | | 1978 | 4,725.5984522148 | | 1977 | 4,623.3415184097 | | 1976 | 4,665.3592058849 | | 1975 | 4,640.2778802245 | | 1974 | 4,576.9829660737 | | 1973 | 4,478.8717055108 | | 1972 | 4,312.504231264 | | 1971 | 4,091.214405417 |
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