| Year | Value | | 2022 | 92.907187803271 | | 2021 | 92.587449551008 | | 2020 | 92.694707876277 | | 2019 | 92.915149259041 | | 2018 | 92.74500490642 | | 2017 | 92.697019975674 | | 2016 | 92.659284039661 | | 2015 | 92.595523234267 | | 2014 | 92.592954124985 | | 2013 | 92.435449120093 | | 2012 | 92.305733799208 | | 2011 | 92.230910548441 | | 2010 | 91.99805055869 | | 2009 | 91.938848369494 | | 2008 | 92.078370150965 | | 2007 | 91.918023542775 | | 2006 | 91.78784981887 | | 2005 | 91.689887413101 | | 2004 | 91.611402043163 | | 2003 | 91.623245671544 | | 2002 | 91.843679824665 | | 2001 | 91.750752696799 | | 2000 | 91.598501110371 | | 1999 | 91.441365895374 | | 1998 | 91.16648556799 | | 1997 | 90.882105718595 | | 1996 | 90.81534475069 | | 1995 | 90.757374901521 | | 1994 | 90.550142253683 | | 1993 | 90.512833012053 | | 1992 | 90.670716820984 | | 1991 | 90.40947748442 |
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