Year | Value | 2023 | 77.725 | 2022 | 76.508 | 2021 | 72.698 | 2020 | 74.757 | 2019 | 76.793 | 2018 | 76.579 | 2017 | 76.418 | 2016 | 76.228 | 2015 | 76.067 | 2014 | 75.95 | 2013 | 75.834 | 2012 | 75.611 | 2011 | 75.18 | 2010 | 74.876 | 2009 | 74.531 | 2008 | 74.206 | 2007 | 73.751 | 2006 | 73.497 | 2005 | 73.156 | 2004 | 72.76 | 2003 | 72.309 | 2002 | 71.537 | 2001 | 71.185 | 2000 | 70.905 | 1999 | 70.913 | 1998 | 70.924 | 1997 | 70.632 | 1996 | 70.209 | 1995 | 69.81 | 1994 | 69.422 | 1993 | 69.083 | 1992 | 68.764 | 1991 | 68.772 | 1990 | 68.701 | 1989 | 68.616 | 1988 | 68.301 | 1987 | 68.166 | 1986 | 68.303 | 1985 | 65.359 | 1984 | 68.308 | 1983 | 68.121 | 1982 | 67.861 | 1981 | 67.189 | 1980 | 66.693 | 1979 | 66.162 | 1978 | 65.827 | 1977 | 65.237 | 1976 | 64.642 | 1975 | 64.012 |
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