| Year | Value | | 2014 | 13,253.821470284 | | 2013 | 13,278.457251226 | | 2012 | 13,200.445022409 | | 2011 | 13,483.993765788 | | 2010 | 13,580.594192854 | | 2009 | 13,164.351992699 | | 2008 | 13,930.915097196 | | 2007 | 13,955.284814959 | | 2006 | 13,871.143483723 | | 2005 | 14,023.679105641 | | 2004 | 13,769.831336435 | | 2003 | 13,691.155094467 | | 2002 | 13,656.442420326 | | 2001 | 13,419.03199127 | | 2000 | 14,001.208337051 | | 1999 | 13,615.616889596 | | 1998 | 13,478.086161816 | | 1997 | 13,261.858487709 | | 1996 | 13,225.947200517 | | 1995 | 13,043.534553964 | | 1994 | 12,845.619641368 | | 1993 | 12,664.914515807 | | 1992 | 12,428.196356271 | | 1991 | 12,537.985944124 | | 1990 | 12,158.089105432 | | 1989 | 12,022.753462229 | | 1988 | 11,801.102821985 | | 1987 | 11,370.198025977 | | 1986 | 10,908.621273108 | | 1985 | 10,849.50957082 | | 1984 | 10,680.14793121 | | 1983 | 10,105.636107541 | | 1982 | 9,880.612557298 | | 1981 | 10,295.155356914 | | 1980 | 10,148.833044921 | | 1979 | 9,964.9941387296 | | 1978 | 9,823.7949842206 | | 1977 | 9,576.9167855058 | | 1976 | 9,173.3969451196 | | 1975 | 8,710.5656024459 | | 1974 | 8,676.856736538 | | 1973 | 8,733.3157602972 | | 1972 | 8,241.7354579064 | | 1971 | 7,675.0576135586 | | 1970 | 7,399.1986783051 | | 1969 | 7,057.8708567086 | | 1968 | 6,539.548430797 | | 1967 | 6,050.5969222906 | | 1966 | 5,754.0395553258 | | 1965 | 5,388.7401217865 | | 1964 | 5,107.5496889411 | | 1963 | 4,806.6674351364 | | 1962 | 4,556.77741382 | | 1961 | 4,310.9050217368 | | 1960 | 4,192.3482099106 |
|