| Year | Value | | 2021 | 78.5957366 | | 2020 | 75.56986637 | | 2019 | 72.45090477 | | 2018 | 70.200565 | | 2017 | 64.04397362 | | 2016 | 53.22677167 | | 2015 | 45.33497615 | | 2014 | 39.35 | | 2013 | 29.95 | | 2012 | 22.73 | | 2011 | 19 | | 2010 | 15.9 | | 2009 | 13.8 | | 2008 | 12.02 | | 2007 | 9.47 | | 2006 | 8.76 | | 2005 | 8.1 | | 2004 | 7.49 | | 2003 | 6.933721953 | | 2002 | 4.626175115 | | 2001 | 1.484221332 | | 2000 | 0.93419002 | | 1999 | 0.378569095 | | 1998 | 0.099815221 | | 1997 | 0.046756094 | | 1996 | 0.01582608 | | 1995 | 0.004179752 | | 1994 | 0.000408332 |
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