| Year | Value | | 2014 | 8,844.687593012 | | 2013 | 8,680.6063607649 | | 2012 | 8,673.9852162012 | | 2011 | 8,651.7552753947 | | 2010 | 8,679.9933500527 | | 2009 | 8,114.3674488574 | | 2008 | 8,401.0483952956 | | 2007 | 8,706.579066944 | | 2006 | 8,720.022084058 | | 2005 | 8,678.1681678443 | | 2004 | 8,314.3253211682 | | 2003 | 8,113.5873060003 | | 2002 | 7,756.318921443 | | 2001 | 7,516.1696002815 | | 2000 | 7,575.435954385 | | 1999 | 7,187.671377866 | | 1998 | 6,965.7540856582 | | 1997 | 6,829.2256294589 | | 1996 | 6,312.685522995 | | 1995 | 6,069.2193459169 | | 1994 | 5,842.5620231129 | | 1993 | 5,499.9726872515 | | 1992 | 5,236.6392649514 | | 1991 | 5,104.8090273846 | | 1990 | 4,983.0463530953 | | 1989 | 4,639.187744656 | | 1988 | 4,398.9897783218 | | 1987 | 4,088.5991691621 | | 1986 | 3,693.6049342699 | | 1985 | 3,444.1330766529 | | 1984 | 3,255.5931602897 | | 1983 | 3,045.8091031871 | | 1982 | 2,814.3191713024 | | 1981 | 2,778.7044951606 | | 1980 | 2,718.3717938893 | | 1979 | 2,529.4734633942 | | 1978 | 2,368.2868796737 | | 1977 | 2,073.7109190212 | | 1976 | 1,884.6204159944 | | 1975 | 1,728.1004154513 | | 1974 | 1,634.2272849583 | | 1973 | 1,599.1792065664 | | 1972 | 1,371.0276900204 | | 1971 | 1,154.8109233755 |
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