| Year | Value | | 2022 | 83.245123956431 | | 2021 | 83.199212599924 | | 2020 | 83.201981038413 | | 2019 | 83.320644576265 | | 2018 | 83.350193726397 | | 2017 | 83.337708289707 | | 2016 | 83.342418211586 | | 2015 | 83.316561963312 | | 2014 | 83.667259030934 | | 2013 | 84.00058613784 | | 2012 | 84.39312592178 | | 2011 | 84.730022254386 | | 2010 | 85.307653898281 | | 2009 | 85.27065407689 | | 2008 | 85.277098628268 | | 2007 | 84.609137669011 | | 2006 | 84.836343832695 | | 2005 | 85.440008290387 | | 2004 | 85.481230841821 | | 2003 | 85.595322407972 | | 2002 | 85.128178509745 | | 2001 | 86.067048365351 | | 2000 | 85.542155636083 | | 1999 | 85.376568620611 | | 1998 | 86.003490936076 | | 1997 | 85.34863506489 | | 1996 | 85.328586223839 | | 1995 | 84.916206723532 | | 1994 | 84.90749729667 | | 1993 | 85.159348653658 | | 1992 | 85.005067570931 | | 1991 | 84.576152708428 |
|