| Year | Value | | 2023 | 122.07967227954 | | 2022 | 120.59868874216 | | 2021 | 113.68932004006 | | 2020 | 112.30749378783 | | 2019 | 113.26564999635 | | 2018 | 112.47078677806 | | 2017 | 111.28680915112 | | 2016 | 110.55094679112 | | 2015 | 110.34333613031 | | 2014 | 111.34592261313 | | 2013 | 109.27500627157 | | 2012 | 106.93852129307 | | 2011 | 103.8087905814 | | 2010 | 100 | | 2009 | 96.854562441607 | | 2008 | 97.68066353218 | | 2007 | 92.615968995577 | | 2006 | 90.585458838371 | | 2005 | 86.5707619496 | | 2004 | 82.810843901847 | | 2003 | 80.587319471143 | | 2002 | 79.159013847253 | | 2001 | 78.610853310517 | | 2000 | 77.352400247306 | | 1999 | 76.140270609735 | | 1998 | 75.924094623416 | | 1997 | 70.303518979137 | | 1996 | 66.559042073263 | | 1995 | 62.90721201867 | | 1994 | 59.448396237574 | | 1993 | 56.591784989795 | | 1992 | 54.777450818908 | | 1991 | 52.600249813843 | | 1990 | 49.759079707944 | | 1989 | 47.002835882384 | | 1988 | 44.613571632714 | | 1987 | 42.954360348222 | | 1986 | 41.920409737254 | | 1985 | 41.162332943539 | | 1984 | 40.185138381945 | | 1983 | 39.840558021007 | | 1982 | 38.409224214711 | | 1981 | 36.490176666987 | | 1980 | 32.388786834364 | | 1979 | 27.057510175486 | | 1978 | 24.620708547242 | | 1977 | 22.812986962196 | | 1976 | 21.201411121049 | | 1975 | 20.35674746757 | | 1974 | 19.326619865032 |
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