| Year | Value | | 2022 | 94.227834849443 | | 2021 | 93.627152856568 | | 2020 | 94.280642528558 | | 2019 | 84.69659271303 | | 2018 | 85.208399862557 | | 2017 | 87.015257179019 | | 2016 | 96.357155252265 | | 2015 | 92.374743307983 | | 2014 | 90.635295503922 | | 2013 | 91.821045806571 | | 2012 | 90.879378753135 | | 2011 | 92.874191523728 | | 2010 | 88.548599013728 | | 2009 | 90.566334329011 | | 2008 | 90.168903927872 | | 2007 | 90.182791501277 | | 2006 | 91.016921679784 | | 2005 | 88.444340240782 | | 2004 | 88.250757206814 | | 2003 | 91.438820188082 | | 2002 | 90.510333751956 | | 2001 | 88.335372723696 | | 2000 | 84.827715237373 | | 1999 | 86.386520717118 | | 1998 | 86.226129734581 | | 1997 | 86.039149700727 | | 1996 | 85.617530743673 | | 1995 | 84.344702315501 | | 1994 | 90.040647958569 | | 1993 | 87.752757823795 | | 1992 | 89.071299104734 | | 1991 | 91.440081259441 | | 1990 | 93.008313993966 | | 1989 | 89.708812689735 | | 1988 | 88.642550646244 | | 1987 | 87.904562820995 | | 1986 | 88.376283109612 | | 1985 | 85.914224015799 | | 1984 | 90.134551945192 | | 1983 | 91.451422985782 | | 1982 | 90.067122178059 | | 1981 | 89.109019951727 | | 1980 | 88.904114552015 | | 1979 | 88.363719161091 | | 1978 | 86.620717651704 | | 1977 | 86.50462962963 | | 1976 | 88.271816650982 | | 1975 | 89.970430752163 |
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