| Year | Value | | 2021 | 6,708,097 | | 2020 | 3,680,874 | | 2019 | 19,461,377 | | 2018 | 18,084,553 | | 2017 | 16,749,271 | | 2016 | 15,076,354 | | 2015 | 14,245,183 | | 2014 | 12,121,912.818 | | 2013 | 11,951,276.822393 | | 2012 | 9,375,669.7396375 | | 2011 | 8,590,839.8497729 | | 2010 | 9,025,035.3118736 | | 2009 | 5,694,547 | | 2008 | 6,147,290 | | 2007 | 7,036,784 | | 2006 | 6,611,915 | | 2005 | 6,938,436 | | 2004 | 6,795,484 | | 2003 | 6,036,360 | | 2002 | 5,662,905 | | 2001 | 5,808,770 | | 2000 | 8,915,627 | | 1999 | 9,191,900 | | 1998 | 8,446,500 | | 1997 | 8,599,800 | | 1996 | 7,913,000 | | 1995 | 6,641,700 | | 1994 | 6,260,700 | | 1993 | 5,104,500 | | 1992 | 5,251,400 | | 1991 | 4,545,900 | | 1990 | 5,369,100 | | 1989 | 4,748,400 | | 1988 | 5,068,800 | | 1987 | 5,405,800 | | 1986 | 5,034,700 | | 1985 | 4,713,200 | | 1984 | 5,163,600 | | 1983 | 4,399,600 | | 1982 | 4,595,900 | | 1981 | 4,890,100 | | 1980 | 5,588,500 | | 1979 | 5,023,500 | | 1978 | 3,946,700 | | 1977 | 3,884,100 | | 1976 | 3,293,600 | | 1975 | 3,299,200 | | 1974 | 2,943,500 | | 1973 | 2,312,700 | | 1972 | 2,358,500 | | 1971 | 2,218,600 | | 1970 | 2,332,000 |
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