| Year | Value | | 2022 | 60.228601643508 | | 2021 | 62.910630068023 | | 2020 | 65.74593903997 | | 2019 | 61.411017891004 | | 2018 | 60.4192620571 | | 2017 | 63.123927549651 | | 2016 | 66.1751702907 | | 2015 | 65.350540288813 | | 2014 | 59.172180604682 | | 2013 | 60.069945894174 | | 2012 | 56.458354179304 | | 2011 | 52.667064562748 | | 2010 | 56.192826876393 | | 2009 | 59.185745682516 | | 2008 | 54.600305968026 | | 2007 | 56.1553336964 | | 2006 | 55.902547151427 | | 2005 | 61.105499853207 | | 2004 | 65.147519708365 | | 2003 | 65.742444457584 | | 2002 | 66.208514401207 | | 2001 | 71.326252964343 | | 2000 | 73.963356920893 | | 1999 | 83.950889488654 | | 1998 | 84.055303766565 | | 1997 | 82.897988658263 | | 1996 | 80.210470819807 | | 1995 | 84.686123901833 | | 1994 | 88.337275378965 | | 1993 | 84.770809330084 |
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