Year | Value | 2021 | 32.573 | 2020 | 33.034 | 2019 | 33.47 | 2018 | 33.955 | 2017 | 34.224 | 2016 | 34.673 | 2015 | 35.357 | 2014 | 36.322 | 2013 | 36.817 | 2012 | 37.207 | 2011 | 37.502 | 2010 | 37.74 | 2009 | 38.1 | 2008 | 37.886 | 2007 | 38.164 | 2006 | 38.657 | 2005 | 38.418 | 2004 | 38.354 | 2003 | 38.611 | 2002 | 38.671 | 2001 | 38.895 | 2000 | 39.169 | 1999 | 39.434 | 1998 | 39.188 | 1997 | 39.255 | 1996 | 39.307 | 1995 | 39.576 | 1994 | 39.848 | 1993 | 40.474 | 1992 | 40.829 | 1991 | 41.303 | 1990 | 41.969 | 1989 | 42.229 | 1988 | 42.756 | 1987 | 43.834 | 1986 | 44.514 | 1985 | 45.427 | 1984 | 46.036 | 1983 | 46.676 | 1982 | 47.161 | 1981 | 47.562 | 1980 | 47.865 | 1979 | 48.15 | 1978 | 48.578 | 1977 | 48.913 | 1976 | 49.067 | 1975 | 49.018 | 1974 | 49.046 | 1973 | 49.168 | 1972 | 49.362 | 1971 | 49.474 | 1970 | 49.478 | 1969 | 49.485 | 1968 | 49.545 | 1967 | 49.695 | 1966 | 49.787 | 1965 | 49.849 | 1964 | 49.887 | 1963 | 50.058 | 1962 | 50.25 | 1961 | 50.355 | 1960 | 50.391 |
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