| Year | Value | | 2021 | 3,307.5308770303 | | 2020 | 3,367.7063832718 | | 2019 | 3,783.4988911748 | | 2018 | 3,818.0327203394 | | 2017 | 3,643.6395104909 | | 2016 | 3,453.5670698359 | | 2015 | 3,347.7415640729 | | 2014 | 3,470.8479268882 | | 2013 | 3,305.2324709499 | | 2012 | 3,088.5905766218 | | 2011 | 2,949.1700438312 | | 2010 | 2,627.002245294 | | 2009 | 2,440.0899532118 | | 2008 | 2,732.2362414492 | | 2007 | 2,563.2578709344 | | 2006 | 2,312.4008585846 | | 2005 | 2,301.8983226094 | | 2004 | 2,089.7945901024 | | 2003 | 1,813.0011698464 | | 2002 | 1,535.0013986506 | | 2001 | 1,460.7845084446 | | 2000 | 1,526.5589074849 | | 1999 | 1,653.4844998937 | | 1998 | 1,515.6010008218 | | 1997 | 1,819.2048272558 | | 1996 | 1,874.7959240381 | | 1995 | 1,757.9347405523 | | 1994 | 1,620.3064213419 | | 1993 | 1,430.4950951258 | | 1992 | 1,366.0242283136 | | 1991 | 1,259.1290932441 | | 1990 | 1,204.8033971417 | | 1989 | 1,095.6372390179 | | 1988 | 1,070.1880406353 | | 1987 | 1,075.0454369772 | | 1986 | 1,157.5565538358 | | 1985 | 1,081.9353739374 | | 1984 | 1,154.2334097203 | | 1983 | 1,128.7489347582 | | 1982 | 1,198.2433353557 | | 1981 | 1,294.8218664189 | | 1980 | 1,280.9899745423 |
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