Year | Value | 2021 | 19,200 | 2020 | 10,108 | 2019 | 36,550 | 2018 | 36,127 | 2017 | 36,946 | 2016 | 38,161 | 2015 | 36,622 | 2014 | 38,386 | 2013 | 38,998 | 2012 | 39,468 | 2011 | 40,329.197802198 | 2010 | 39,318.791597625 | 2009 | 32,490 | 2008 | 30,804 | 2007 | 29,415 | 2006 | 26,546 | 2005 | 19,689 | 2004 | 17,958 | 2003 | 15,354 | 2002 | 16,369 | 2001 | 15,893 | 2000 | 16,447 | 1999 | 15,900 | 1998 | 15,400 | 1997 | 16,700 | 1996 | 17,100 | 1995 | 16,800 | 1994 | 16,000 | 1993 | 15,500 | 1992 | 14,300 | 1991 | 11,000 | 1990 | 14,100 | 1989 | 17,400 | 1988 | 15,500 | 1987 | 15,000 | 1986 | 14,800 | 1985 | 15,200 | 1984 | 15,500 | 1983 | 16,200 | 1982 | 17,100 | 1981 | 16,500 | 1980 | 14,000 | 1979 | 11,900 | 1978 | 10,400 | 1977 | 9,300 | 1976 | 8,700 | 1975 | 7,000 | 1974 | 5,600 | 1973 | 4,500 | 1972 | 4,100 | 1971 | 4,400 | 1970 | 4,200 |
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