| Year | Value | | 2021 | 1,769,289.853 | | 2020 | 1,252,229.27 | | 2019 | 2,771,658.5831284 | | 2018 | 2,740,715.2921387 | | 2017 | 2,685,336 | | 2016 | 2,757,267 | | 2015 | 2,832,631 | | 2014 | 2,771,753.9966472 | | 2013 | 2,675,506.4150769 | | 2012 | 2,503,306.4114108 | | 2011 | 2,384,451.9656857 | | 2010 | 2,255,941.2373442 | | 2009 | 1,797,292 | | 2008 | 1,755,794 | | 2007 | 1,787,182 | | 2006 | 1,649,988 | | 2005 | 1,611,517 | | 2004 | 1,543,862 | | 2003 | 1,528,729 | | 2002 | 1,720,239 | | 2001 | 1,875,770 | | 2000 | 1,795,191 | | 1999 | 1,938,700 | | 1998 | 1,777,500 | | 1997 | 1,701,200 | | 1996 | 1,498,300 | | 1995 | 1,430,600 | | 1994 | 1,412,700 | | 1993 | 1,353,900 | | 1992 | 1,260,800 | | 1991 | 1,218,400 | | 1990 | 1,192,900 | | 1989 | 1,181,100 | | 1988 | 1,160,400 | | 1987 | 1,175,700 | | 1986 | 1,154,500 | | 1985 | 1,136,900 | | 1984 | 1,162,800 | | 1983 | 1,120,000 | | 1982 | 1,029,000 | | 1981 | 918,700 | | 1980 | 933,500 | | 1979 | 859,000 | | 1978 | 766,700 | | 1977 | 756,300 | | 1976 | 770,800 | | 1975 | 749,400 | | 1974 | 728,300 | | 1973 | 689,000 | | 1972 | 675,900 | | 1971 | 663,000 | | 1970 | 696,700 |
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