| Year | Value | | 2022 | 90.325419724065 | | 2021 | 88.918025547973 | | 2020 | 89.741409666308 | | 2019 | 88.602656857192 | | 2018 | 89.02260565575 | | 2017 | 89.660619716636 | | 2016 | 100.42659736894 | | 2015 | 105.28561979667 | | 2014 | 100.57836642955 | | 2013 | 103.9912430892 | | 2012 | 94.378014124424 | | 2011 | 96.696859045351 | | 2010 | 92.538759703021 | | 2009 | 103.47715695105 | | 2008 | 94.685621693795 | | 2007 | 100.59944515814 | | 2006 | 97.174280467052 | | 2005 | 80.790587915974 | | 2004 | 80.463013249295 | | 2003 | 77.61195737288 | | 2002 | 87.954305095221 | | 2001 | 84.962388996078 | | 2000 | 83.961183310175 | | 1999 | 84.545062868115 | | 1998 | 86.430368290473 | | 1997 | 82.27157582855 | | 1996 | 84.355328666557 | | 1995 | 81.997642487599 | | 1994 | 82.117283256109 | | 1993 | 79.869106326072 | | 1992 | 79.978361562909 | | 1991 | 77.870564629029 | | 1990 | 77.840732746379 | | 1989 | 81.506595315866 | | 1988 | 87.115683847582 | | 1987 | 82.810038874914 | | 1986 | 82.057417706298 |
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