| Year | Value | | 2014 | 7,035.4829747168 | | 2013 | 7,217.529089155 | | 2012 | 7,270.1525230273 | | 2011 | 7,281.2721741716 | | 2010 | 7,264.3225907355 | | 2009 | 6,817.1583982366 | | 2008 | 7,187.7640090962 | | 2007 | 7,229.0899129477 | | 2006 | 7,212.4374476876 | | 2005 | 7,138.2214852918 | | 2004 | 7,108.962524477 | | 2003 | 7,009.7264919686 | | 2002 | 6,900.7805270299 | | 2001 | 6,762.6533964664 | | 2000 | 6,635.4214059667 | | 1999 | 6,505.1329994236 | | 1998 | 6,479.4902494838 | | 1997 | 6,427.7987684027 | | 1996 | 6,403.3337259769 | | 1995 | 6,327.709753995 | | 1994 | 6,244.9572282581 | | 1993 | 6,288.4163500526 | | 1992 | 6,445.8739998927 | | 1991 | 6,564.7971947273 | | 1990 | 6,639.7316914605 | | 1989 | 6,835.3299082124 | | 1988 | 6,776.307911873 | | 1987 | 6,666.2195952925 | | 1986 | 6,530.2387135347 | | 1985 | 6,448.5398592336 | | 1984 | 6,239.9718156041 | | 1983 | 5,965.4581934875 | | 1982 | 5,822.0273593248 | | 1981 | 5,832.0648707024 | | 1980 | 5,797.4997527098 | | 1979 | 5,786.1272157217 | | 1978 | 5,574.7452165925 | | 1977 | 5,285.2607863166 | | 1976 | 5,146.9325777938 | | 1975 | 4,743.9448331011 | | 1974 | 4,803.4232035882 | | 1973 | 4,654.9850483931 | | 1972 | 4,335.7696247475 | | 1971 | 4,064.4547161243 | | 1970 | 3,834.1784073282 | | 1969 | 2,815.2213482273 | | 1968 | 2,579.7499153689 | | 1967 | 2,362.9089428675 | | 1966 | 2,300.4997982319 | | 1965 | 2,194.2060611981 | | 1964 | 2,060.547353827 | | 1963 | 1,916.9275279677 | | 1962 | 1,790.6868774264 | | 1961 | 1,683.4149131441 | | 1960 | 1,586.7494152982 |
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