Year | Value | 2021 | 68.877 | 2020 | 69.743 | 2019 | 69.728 | 2018 | 69.664 | 2017 | 69.656 | 2016 | 69.137 | 2015 | 68.932 | 2014 | 69.347 | 2013 | 69.38 | 2012 | 69.412 | 2011 | 69.521 | 2010 | 69.271 | 2009 | 69.046 | 2008 | 68.885 | 2007 | 68.727 | 2006 | 68.797 | 2005 | 68.666 | 2004 | 68.484 | 2003 | 68.302 | 2002 | 67.98 | 2001 | 68.629 | 2000 | 68.678 | 1999 | 69.193 | 1998 | 69.117 | 1997 | 68.817 | 1996 | 68.853 | 1995 | 68.771 | 1994 | 68.652 | 1993 | 68.454 | 1992 | 68.41 | 1991 | 68.316 | 1990 | 68.213 | 1989 | 68.026 | 1988 | 67.98 | 1987 | 67.773 | 1986 | 67.556 | 1985 | 67.203 | 1984 | 66.518 | 1983 | 65.862 | 1982 | 65.266 | 1981 | 65.215 | 1980 | 65.374 | 1979 | 65.763 | 1978 | 65.427 | 1977 | 65.191 | 1976 | 64.912 | 1975 | 64.713 | 1974 | 64.51 | 1973 | 64.025 | 1972 | 64.79 | 1971 | 64.676 | 1970 | 64.564 | 1969 | 64.366 | 1968 | 64.369 | 1967 | 63.959 | 1966 | 63.519 | 1965 | 62.959 | 1964 | 62.352 | 1963 | 61.384 | 1962 | 60.589 | 1961 | 59.59 | 1960 | 58.574 |
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