| Year | Value | | 2021 | 33,922 | | 2020 | 20,436 | | 2019 | 62,113.332 | | 2018 | 66,712 | | 2017 | 63,315 | | 2016 | 55,261 | | 2015 | 45,688 | | 2014 | 47,927.4 | | 2013 | 58,474.09 | | 2012 | 73,378.942618274 | | 2011 | 76,652.268181818 | | 2010 | 66,038 | | 2009 | 58,756 | | 2008 | 52,509 | | 2007 | 30,029 | | 2006 | 48,562 | | 2005 | 41,911 | | 2004 | 42,374 | | 2003 | 39,778 | | 2002 | 26,859 | | 2001 | 32,864 | | 2000 | 27,973 | | 1999 | 29,500 | | 1998 | 29,800 | | 1997 | 30,600 | | 1996 | 27,700 | | 1995 | 22,600 | | 1994 | 11,400 | | 1993 | 26,400 | | 1992 | 45,400 |
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