| Year | Value | | 2014 | -102.96411204292 | | 2013 | -227.78894955333 | | 2012 | -403.05906845193 | | 2011 | -138.44085396941 | | 2010 | -399.06501793324 | | 2009 | -418.08088411587 | | 2008 | -502.21358035235 | | 2007 | -546.95923995273 | | 2006 | -483.95056328219 | | 2005 | -450.05975632832 | | 2004 | -405.67705305559 | | 2003 | -360.98893746263 | | 2002 | -339.24198119391 | | 2001 | -358.83594143901 | | 2000 | -379.69678892399 | | 1999 | -378.85280549662 | | 1998 | -430.277119382 | | 1997 | -420.55375409632 | | 1996 | -425.28186351387 | | 1995 | -452.22617268408 | | 1994 | -467.37393304084 | | 1993 | -533.37155092895 | | 1992 | -591.79698034685 | | 1991 | -620.9254458189 | | 1990 | -555.22770124239 | | 1989 | -431.94848760345 | | 1988 | -454.69523070338 | | 1987 | -401.20669445547 | | 1986 | -464.17103104934 | | 1985 | -464.73185995341 | | 1984 | -548.79367269475 | | 1983 | -588.17160247533 | | 1982 | -630.37441133913 | | 1981 | -744.92985463353 | | 1980 | -1,269.7048828221 | | 1979 | -1,989.5969145516 | | 1978 | -2,121.9558117892 | | 1977 | -2,516.7870274999 | | 1976 | -2,974.2787260469 | | 1975 | -2,049.8689414409 | | 1974 | -2,665.9233030082 | | 1973 | -4,232.4159349804 | | 1972 | -5,127.2952348883 | | 1971 | -8,657.8321386606 |
|