| Year | Value | | 2022 | 95.603904506405 | | 2021 | 95.568215324873 | | 2020 | 95.520325797833 | | 2019 | 95.707168410957 | | 2018 | 95.704186991521 | | 2017 | 95.727042894568 | | 2016 | 95.755043676444 | | 2015 | 95.7448319076 | | 2014 | 95.731600797294 | | 2013 | 95.706195745315 | | 2012 | 95.67736450783 | | 2011 | 95.629000133695 | | 2010 | 95.560395417246 | | 2009 | 95.14726582849 | | 2008 | 94.558318915105 | | 2007 | 94.002154878067 | | 2006 | 93.375639215437 | | 2005 | 92.688365425774 | | 2004 | 91.855894592126 | | 2003 | 90.98126669424 | | 2002 | 89.987077181138 | | 2001 | 88.803909204758 | | 2000 | 87.457010611616 | | 1999 | 87.133488431974 | | 1998 | 86.660452461329 | | 1997 | 86.419694801262 | | 1996 | 86.005895195908 | | 1995 | 85.929361051241 | | 1994 | 85.808747366418 | | 1993 | 85.764004634559 | | 1992 | 85.854200866014 | | 1991 | 85.926793178013 |
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