Year | Value | 2021 | 33.934 | 2020 | 34.197 | 2019 | 34.554 | 2018 | 35.007 | 2017 | 35.863 | 2016 | 35.959 | 2015 | 36.282 | 2014 | 36.6 | 2013 | 37.137 | 2012 | 37.742 | 2011 | 38.435 | 2010 | 38.815 | 2009 | 39.179 | 2008 | 39.676 | 2007 | 40.248 | 2006 | 40.91 | 2005 | 41.602 | 2004 | 42.227 | 2003 | 43.015 | 2002 | 43.53 | 2001 | 44.194 | 2000 | 44.753 | 1999 | 44.991 | 1998 | 45.157 | 1997 | 44.978 | 1996 | 44.831 | 1995 | 45 | 1994 | 44.89 | 1993 | 45.436 | 1992 | 46.009 | 1991 | 46.429 | 1990 | 46.754 | 1989 | 47.084 | 1988 | 46.023 | 1987 | 46.673 | 1986 | 47.823 | 1985 | 48.887 | 1984 | 50.021 | 1983 | 50.975 | 1982 | 51.736 | 1981 | 52.355 | 1980 | 52.77 | 1979 | 52.834 | 1978 | 52.507 | 1977 | 52.496 | 1976 | 51.561 | 1975 | 51.866 | 1974 | 52.157 | 1973 | 52.317 | 1972 | 52.393 | 1971 | 52.636 | 1970 | 52.842 | 1969 | 53.166 | 1968 | 53.473 | 1967 | 53.72 | 1966 | 53.943 | 1965 | 54.168 | 1964 | 54.405 | 1963 | 54.554 | 1962 | 54.652 | 1961 | 54.706 | 1960 | 54.766 |
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