| Year | Value | | 2021 | 65.9773785 | | 2020 | 59.94010155 | | 2019 | 47.47481911 | | 2018 | 44.2861422 | | 2017 | 43.83227607 | | 2016 | 39.6975146 | | 2015 | 37.49 | | 2014 | 34.6 | | 2013 | 36.99 | | 2012 | 35.34 | | 2011 | 30 | | 2010 | 22.4 | | 2009 | 16.8 | | 2008 | 12.5 | | 2007 | 10.49924432 | | 2006 | 6.200671255 | | 2005 | 5.227583957 | | 2004 | 4.439924601 | | 2003 | 3.508596401 | | 2002 | 3.117192947 | | 2001 | 2.120462534 | | 2000 | 1.442763585 | | 1999 | 0.981815187 | | 1998 | 0.626484062 | | 1997 | 0.447839036 | | 1996 | 0.196081174 | | 1995 | 0.066807568 |
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