| Year | Value | | 2022 | 84.931630802855 | | 2021 | 84.510394316932 | | 2020 | 84.561340982077 | | 2019 | 84.563228278721 | | 2018 | 84.831226559244 | | 2017 | 84.887073835836 | | 2016 | 84.916585607576 | | 2015 | 85.053611519703 | | 2014 | 85.155476978558 | | 2013 | 85.250753023965 | | 2012 | 85.477434758653 | | 2011 | 85.657786514691 | | 2010 | 85.732097786547 | | 2009 | 85.970990735911 | | 2008 | 86.217309448804 | | 2007 | 85.721573517742 | | 2006 | 86.119739365721 | | 2005 | 86.158057372069 | | 2004 | 85.847707868471 | | 2003 | 86.163054559805 | | 2002 | 86.986801829971 | | 2001 | 87.963758702242 | | 2000 | 87.964283541634 | | 1999 | 87.867085097461 | | 1998 | 87.92685266389 | | 1997 | 87.928688456305 | | 1996 | 87.916317165836 | | 1995 | 87.889164064463 | | 1994 | 87.837680484397 | | 1993 | 87.791040377247 | | 1992 | 87.747859480298 | | 1991 | 87.695140804511 |
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