| Year | Value | | 2021 | 75.62650476 | | 2020 | 71.49017499 | | 2019 | 69.63210927 | | 2018 | 56.6595668 | | 2017 | 53.03178861 | | 2016 | 59.540446 | | 2015 | 57.43104299 | | 2014 | 44.39 | | 2013 | 43.46 | | 2012 | 39.75 | | 2011 | 37.17629541 | | 2010 | 31.05 | | 2009 | 26.34 | | 2008 | 21.71 | | 2007 | 20.81 | | 2006 | 19.52 | | 2005 | 17.21 | | 2004 | 14.1 | | 2003 | 12.9 | | 2002 | 11.9 | | 2001 | 7.038023117 | | 2000 | 5.081384153 | | 1999 | 1.857436221 | | 1998 | 1.265783278 | | 1997 | 0.62731154 | | 1996 | 0.20040628 | | 1995 | 0.10256419 | | 1994 | 0.043339167 | | 1993 | 0.028305042 | | 1992 | 0.01730781 | | 1991 | 0.005880695 |
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