Year | Value | 2021 | 6.585 | 2020 | 6.836 | 2019 | 6.583 | 2018 | 6.639 | 2017 | 6.537 | 2016 | 6.574 | 2015 | 6.53 | 2014 | 6.567 | 2013 | 6.447 | 2012 | 6.379 | 2011 | 6.356 | 2010 | 6.377 | 2009 | 6.418 | 2008 | 6.562 | 2007 | 6.691 | 2006 | 6.769 | 2005 | 6.869 | 2004 | 6.741 | 2003 | 6.797 | 2002 | 6.88 | 2001 | 6.932 | 2000 | 6.949 | 1999 | 7.166 | 1998 | 7.372 | 1997 | 7.637 | 1996 | 7.735 | 1995 | 7.788 | 1994 | 7.866 | 1993 | 7.961 | 1992 | 8.027 | 1991 | 8.064 | 1990 | 8.257 | 1989 | 8.495 | 1988 | 8.66 | 1987 | 8.905 | 1986 | 9.1 | 1985 | 9.318 | 1984 | 9.364 | 1983 | 9.525 | 1982 | 9.586 | 1981 | 9.632 | 1980 | 9.824 | 1979 | 10.055 | 1978 | 10.249 | 1977 | 10.488 | 1976 | 10.628 | 1975 | 10.728 | 1974 | 10.915 | 1973 | 11.198 | 1972 | 11.499 | 1971 | 11.827 | 1970 | 12.155 | 1969 | 12.598 | 1968 | 13.085 | 1967 | 13.502 | 1966 | 14.071 | 1965 | 14.619 | 1964 | 15.131 | 1963 | 15.658 | 1962 | 16.193 | 1961 | 16.619 | 1960 | 17.041 |
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