| Year | Value | | 2022 | 68.728216419008 | | 2021 | 70.978424529369 | | 2020 | 72.913386564702 | | 2019 | 69.470239106186 | | 2018 | 71.527405288357 | | 2017 | 71.048940387254 | | 2016 | 73.315837830417 | | 2015 | 75.210486804874 | | 2014 | 77.555824589723 | | 2013 | 81.580567230367 | | 2012 | 85.781855684768 | | 2011 | 84.720425791297 | | 2010 | 84.216345640603 | | 2009 | 92.00415959184 | | 2008 | 85.380149207875 | | 2007 | 83.100472005592 | | 2006 | 85.122554943452 | | 2005 | 94.853596133801 | | 2004 | 85.776913250494 | | 2003 | 83.306550235994 | | 2002 | 77.202602692098 | | 2001 | 75.657315646132 | | 2000 | 77.05782786125 | | 1999 | 79.307232744375 | | 1998 | 76.189768597944 |
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