| Year | Value | | 2021 | 2,846.6405075142 | | 2020 | 2,726.4227472273 | | 2019 | 3,140.9071789864 | | 2018 | 3,216.4348546122 | | 2017 | 3,339.9349312492 | | 2016 | 3,297.7433062191 | | 2015 | 3,359.1176372623 | | 2014 | 4,214.8452362708 | | 2013 | 4,255.8865013467 | | 2012 | 4,325.0090299713 | | 2011 | 4,120.8901866071 | | 2010 | 3,483.2360459261 | | 2009 | 2,985.0687032464 | | 2008 | 3,539.0496689545 | | 2007 | 2,820.3986242387 | | 2006 | 2,357.4420544952 | | 2005 | 2,099.7720894224 | | 2004 | 1,889.0614256769 | | 2003 | 1,571.7244958436 | | 2002 | 1,351.8682404661 | | 2001 | 1,345.1049407452 | | 2000 | 1,298.7950239979 | | 1999 | 1,224.2143092352 | | 1998 | 1,289.6823510618 | | 1997 | 1,254.4264786854 | | 1996 | 1,205.7165592947 | | 1995 | 1,125.292728766 | | 1994 | 1,194.7257422062 | | 1993 | 1,450.0312601419 | | 1992 | 1,440.1577552041 | | 1991 | 1,355.5517363087 | | 1990 | 1,896.7029085452 | | 1989 | 1,791.8158052048 | | 1988 | 1,953.9334681575 | | 1987 | 2,277.0708471208 | | 1986 | 2,295.9173297939 | | 1985 | 2,032.3564609427 | | 1984 | 1,941.937589366 | | 1983 | 1,790.8228667944 | | 1982 | 1,697.1798276003 | | 1981 | 1,612.9208816727 | | 1980 | 1,484.2472268221 | | 1979 | 1,088.4458954564 | | 1978 | 1,088.1672553554 | | 1977 | 847.82180125331 | | 1976 | 786.34468189886 | | 1975 | 747.74152776901 | | 1974 | 639.88374701358 | | 1973 | 483.71413148773 | | 1972 | 397.63746452082 | | 1971 | 310.6100690452 | | 1970 | 296.15917253413 |
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