| Year | Value | | 2021 | 6,359.1732048952 | | 2020 | 5,713.3945818416 | | 2019 | 5,897.3838884711 | | 2018 | 5,518.2113842664 | | 2017 | 5,376.0324061361 | | 2016 | 4,969.510691285 | | 2015 | 5,129.6519942789 | | 2014 | 4,871.7922033623 | | 2013 | 4,812.8317286404 | | 2012 | 4,633.6576147708 | | 2011 | 4,153.9359759221 | | 2010 | 3,920.4166693857 | | 2009 | 3,744.887244951 | | 2008 | 3,587.1351956166 | | 2007 | 3,222.512401802 | | 2006 | 2,735.6682621296 | | 2005 | 861.04992799178 | | 2004 | 800.54968479254 | | 2003 | 761.02957101628 | | 2002 | 749.84334736629 | | 2001 | 751.9910477026 | | 2000 | 751.96169349518 | | 1999 | 674.22884951605 | | 1998 | 716.24155320453 | | 1997 | 665.60101077431 | | 1996 | 634.4596093412 | | 1995 | 469.90939207066 | | 1994 | 432.56687469218 | | 1993 | 372.75140250401 | | 1992 | 257.48865402521 | | 1991 | 193.63083924178 | | 1990 | 299.90169730359 | | 1989 | 265.28178494292 | | 1988 | 342.01778618611 | | 1987 | 260.4905475204 | | 1986 | 447.13595003475 | | 1985 | 410.58380988495 | | 1984 | 376.64150235505 | | 1983 | 407.05499394543 | | 1982 | 340.92980529377 | | 1981 | 512.59873474518 | | 1980 | 573.76780956887 |
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