| Year | Value | | 2022 | 97.86011812 | | 2021 | 98.8658506 | | 2020 | 96.54914573 | | 2019 | 98.04643475 | | 2018 | 97.31920437 | | 2017 | 97.09936216 | | 2016 | 96.96778525 | | 2015 | 96.33050162 | | 2014 | 95.99 | | 2013 | 94.6297 | | 2012 | 92.26001172 | | 2011 | 89.81001339 | | 2010 | 88.72 | | 2009 | 86.84 | | 2008 | 85.02 | | 2007 | 85.03 | | 2006 | 86.65 | | 2005 | 82.74 | | 2004 | 80.93 | | 2003 | 76.26 | | 2002 | 64.25 | | 2001 | 42.95752472 | | 2000 | 39.17243086 | | 1999 | 30.59204065 | | 1998 | 22.66874615 | | 1997 | 11.38200494 | | 1996 | 5.714987841 | | 1995 | 3.82565642 | | 1994 | 1.34430775 | | 1993 | 0.578329976 | | 1992 | 0.386913951 | | 1991 | 0.194056515 | | 1990 | 0.097277268 |
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