| Year | Value | | 2014 | 3,305.8885277498 | | 2013 | 3,215.1056499675 | | 2012 | 3,056.1826985361 | | 2011 | 2,944.4408690781 | | 2010 | 2,728.9766818777 | | 2009 | 2,494.4402518089 | | 2008 | 2,434.0424274602 | | 2007 | 2,353.050110148 | | 2006 | 2,167.8345013259 | | 2005 | 1,990.4098190026 | | 2004 | 1,863.933844409 | | 2003 | 1,727.469380866 | | 2002 | 1,596.9937797349 | | 2001 | 1,519.0570270694 | | 2000 | 1,479.92972608 | | 1999 | 1,402.4275511523 | | 1998 | 1,368.5555972385 | | 1997 | 1,357.3067101834 | | 1996 | 1,329.1078519546 | | 1995 | 1,284.9461951105 | | 1994 | 1,253.7458595713 | | 1993 | 1,246.9430128485 | | 1992 | 1,247.228717158 | | 1991 | 1,258.1201969517 | | 1990 | 1,250.4763323372 | | 1989 | 711.80497016805 | | 1988 | 686.21648335325 | | 1987 | 651.62890994439 | | 1986 | 619.314163272 | | 1985 | 585.87245463184 | | 1984 | 557.45824157768 | | 1983 | 522.24211469428 | | 1982 | 499.75923548248 | | 1981 | 478.31217735266 | | 1980 | 467.60906594278 | | 1979 | 442.11235671438 | | 1978 | 408.802731965 | | 1977 | 375.52707109253 | | 1976 | 348.84175742296 | | 1975 | 330.29544094687 | | 1974 | 303.37799894645 | | 1973 | 293.03464497676 | | 1972 | 273.05496399718 | | 1971 | 254.30827576484 |
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