| Year | Value | | 2014 | 1,431.1643414607 | | 2013 | 1,283.7144397734 | | 2012 | 1,213.072692784 | | 2011 | 1,109.3263105278 | | 2010 | 1,028.9435843621 | | 2009 | 912.53853665423 | | 2008 | 808.61251123737 | | 2007 | 733.73448745219 | | 2006 | 650.32554394307 | | 2005 | 574.69083500963 | | 2004 | 488.37809209186 | | 2003 | 437.58992314592 | | 2002 | 381.73510609344 | | 2001 | 330.31488712095 | | 2000 | 289.9198596395 | | 1999 | 256.26022152838 | | 1998 | 235.94414427553 | | 1997 | 205.76239087641 | | 1996 | 182.53033152418 | | 1995 | 155.49265711042 | | 1994 | 131.36354769412 | | 1993 | 113.82985695892 | | 1992 | 103.44074525367 | | 1991 | 100.33818605997 | | 1990 | 96.782948829094 | | 1989 | 93.162349439279 | | 1988 | 86.12139440641 | | 1987 | 79.018646213084 | | 1986 | 72.24632511137 | | 1985 | 69.234393834491 | | 1984 | 66.190851578521 | | 1983 | 57.18150201563 | | 1982 | 57.916147879447 | | 1981 | 55.563340236624 | | 1980 | 55.316135490172 | | 1979 | 54.17566563767 | | 1978 | 55.383022713075 | | 1977 | 54.817916089534 | | 1976 | 47.878507684635 | | 1975 | 40.323940481012 | | 1974 | 35.18618327692 | | 1973 | 40.831982495665 | | 1972 | 39.083479647745 | | 1971 | 41.801983306049 |
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