| Year | Value | | 2014 | -83.525395995276 | | 2013 | -100.23658739991 | | 2012 | -110.15781129154 | | 2011 | -111.31414255259 | | 2010 | -124.3167716362 | | 2009 | -126.6315738105 | | 2008 | -130.15555239243 | | 2007 | -137.29620622395 | | 2006 | -137.55299877335 | | 2005 | -136.50872976419 | | 2004 | -138.69749139326 | | 2003 | -122.7038407633 | | 2002 | -132.76195030596 | | 2001 | -150.76496407583 | | 2000 | -158.78314990366 | | 1999 | -155.8478917648 | | 1998 | -153.33384264423 | | 1997 | -138.38451526157 | | 1996 | -125.98763147346 | | 1995 | -117.92684117138 | | 1994 | -111.92010477673 | | 1993 | -112.89265995298 | | 1992 | -108.73990051255 | | 1991 | -110.9570204969 | | 1990 | -135.95302818655 | | 1989 | -165.31503159889 | | 1988 | -160.69054117899 | | 1987 | -138.12750895805 | | 1986 | -133.1936824939 | | 1985 | -128.07230321449 | | 1984 | -130.00743585498 | | 1983 | -118.65404807548 | | 1982 | -134.08410650625 | | 1981 | -149.16940753891 | | 1980 | -248.91489480593 | | 1979 | -312.17687633897 | | 1978 | -275.30879787826 | | 1977 | -295.7842392648 | | 1976 | -311.39879000975 | | 1975 | -292.6956773483 | | 1974 | -339.23960091548 | | 1973 | -399.89997202114 | | 1972 | -382.0081345232 | | 1971 | -420.12889824274 |
|