| Year | Value | | 2023 | 93.9564 | | 2022 | 94 | | 2021 | 93.9371 | | 2020 | 92.3 | | 2019 | 91.9129 | | 2018 | 94.64 | | 2017 | 92.7014 | | 2016 | 91.16 | | 2015 | 90 | | 2014 | 87.12 | | 2013 | 85.8 | | 2012 | 83 | | 2011 | 83 | | 2010 | 80.3 | | 2009 | 80.3 | | 2008 | 76.7 | | 2007 | 73.2 | | 2006 | 72.4 | | 2005 | 71.66 | | 2004 | 65.956 | | 2003 | 64.2 | | 2002 | 61.5933 | | 2001 | 60.2 | | 2000 | 51.3 | | 1999 | 36.2 | | 1998 | 24.9 | | 1997 | 15.1 | | 1996 | 6.76 | | 1995 | 4.16 | | 1994 | 2.38 | | 1993 | 1.18 | | 1992 | 0.916 | | 1991 | 0.57 | | 1990 | 0.361 |
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