| Year | Value | | 2022 | 83.649166049164 | | 2021 | 84.359964570116 | | 2020 | 85.710916236624 | | 2019 | 85.671719668837 | | 2018 | 85.263214059539 | | 2017 | 85.115034019516 | | 2016 | 84.994021136509 | | 2015 | 85.024911806891 | | 2014 | 84.756735610431 | | 2013 | 84.590885270786 | | 2012 | 84.666960320467 | | 2011 | 84.512237629065 | | 2010 | 84.290099165934 | | 2009 | 84.749861818216 | | 2008 | 84.121789452891 | | 2007 | 83.851102785973 | | 2006 | 84.079390022031 | | 2005 | 83.97940120938 | | 2004 | 83.773449247517 | | 2003 | 82.489869838043 | | 2002 | 83.05327598 | | 2001 | 82.841161389727 | | 2000 | 81.984451709029 | | 1999 | 82.018008706996 | | 1998 | 82.188622300815 | | 1997 | 81.623200523976 | | 1996 | 82.175838090537 | | 1995 | 82.146443074685 | | 1994 | 82.09556433781 | | 1993 | 82.065418108714 | | 1992 | 82.044221890668 | | 1991 | 81.974097151591 |
|