| Year | Value | | 2014 | -206.19471212828 | | 2013 | -209.61606178175 | | 2012 | -205.86980717924 | | 2011 | -215.75700493312 | | 2010 | -258.43693663493 | | 2009 | -295.95978863383 | | 2008 | -277.98098950647 | | 2007 | -235.68525113046 | | 2006 | -292.77202115016 | | 2005 | -501.52743957841 | | 2004 | -559.38468490563 | | 2003 | -595.1635041639 | | 2002 | -674.15645229039 | | 2001 | -740.75164486216 | | 2000 | -697.03130932975 | | 1999 | -666.79967956457 | | 1998 | -661.88058768568 | | 1997 | -663.79449120284 | | 1996 | -699.60957089473 | | 1995 | -697.36680215512 | | 1994 | -665.60840121661 | | 1993 | -647.05639256212 | | 1992 | -664.69528277306 | | 1991 | -576.33110662432 | | 1990 | -807.85673181572 | | 1989 | -1,252.368499366 | | 1988 | -1,422.476857922 | | 1987 | -1,278.555793907 | | 1986 | -1,422.7794384689 | | 1985 | -1,167.1759432554 | | 1984 | -896.02850368127 | | 1983 | -1,416.5722317453 | | 1982 | -1,106.1206442868 | | 1981 | -1,678.8452296286 | | 1980 | -1,210.9050054481 | | 1979 | -1,749.3596631679 | | 1978 | -2,863.9247296344 | | 1977 | -2,265.231659143 | | 1976 | -4,940.4590299365 | | 1975 | -7,333.4830604616 | | 1974 | -10,003.213837617 | | 1973 | -15,639.376054836 | | 1972 | -16,718.714438429 | | 1971 | -17,632.766112792 |
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