Year | Value | 2024 | 82.59213271572 | 2023 | 81.966934017087 | 2022 | 81.466315525229 | 2021 | 79.915585000319 | 2020 | 83.279153919719 | 2019 | 85.127628686318 | 2018 | 84.511162754783 | 2017 | 84.656211035148 | 2016 | 84.630777018009 | 2015 | 83.741617233088 | 2014 | 82.113109419648 | 2013 | 80.607729078586 | 2012 | 79.941970100686 | 2011 | 78.943108699811 | 2010 | 79.239687004107 | 2009 | 81.607098306728 | 2008 | 78.570185537512 | 2007 | 78.817935184296 | 2006 | 79.476593404683 | 2005 | 79.394253226318 | 2004 | 78.674161107518 | 2003 | 80.922128910893 | 2002 | 81.70809737598 | 2001 | 83.45100338712 | 2000 | 83.360546079648 | 1999 | 84.462810203558 | 1998 | 84.212832344272 | 1997 | 84.844924489108 | 1996 | 84.90822573366 | 1995 | 84.634363576392 | 1994 | 77.503043995582 | 1993 | 77.746421320755 | 1992 | 78.58221152436 | 1991 | 79.468035696513 | 1990 | 78.593414786935 | 1989 | 69.628871301717 | 1988 | 77.244131420022 | 1987 | 77.327617869886 | 1986 | 82.009983084138 | 1985 | 79.973812624461 | 1984 | 87.272257707056 | 1983 | 86.726502827067 | 1982 | 82.611820576089 | 1981 | 78.956398014966 | 1980 | 78.119241471242 | 1979 | 80.588002636998 | 1978 | 78.419549419676 | 1977 | 78.5192116027 | 1976 | 79.026587457182 | 1975 | 73.848381795621 |
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