Year | Value | 2021 | 34.842 | 2020 | 35.603 | 2019 | 36.323 | 2018 | 37.011 | 2017 | 38.124 | 2016 | 39.479 | 2015 | 41.321 | 2014 | 42.356 | 2013 | 43.402 | 2012 | 44.413 | 2011 | 45.583 | 2010 | 46.691 | 2009 | 46.681 | 2008 | 46.562 | 2007 | 46.525 | 2006 | 46.38 | 2005 | 46.03 | 2004 | 45.297 | 2003 | 44.485 | 2002 | 43.807 | 2001 | 42.882 | 2000 | 42.473 | 1999 | 42.005 | 1998 | 41.346 | 1997 | 41.867 | 1996 | 43.858 | 1995 | 44.504 | 1994 | 39.132 | 1993 | 46.026 | 1992 | 45.702 | 1991 | 46.128 | 1990 | 46.545 | 1989 | 46.912 | 1988 | 47.248 | 1987 | 47.474 | 1986 | 47.762 | 1985 | 48.338 | 1984 | 48.763 | 1983 | 49.495 | 1982 | 49.673 | 1981 | 50.47 | 1980 | 48.896 | 1979 | 48.865 | 1978 | 48.16 | 1977 | 47.728 | 1976 | 47.499 | 1975 | 47.371 | 1974 | 46.718 | 1973 | 46.325 | 1972 | 47.633 | 1971 | 47.455 | 1970 | 47.339 | 1969 | 47.45 | 1968 | 47.192 | 1967 | 47.124 | 1966 | 46.85 | 1965 | 46.896 | 1964 | 46.25 | 1963 | 46.368 | 1962 | 46.522 | 1961 | 46.265 | 1960 | 46.501 |
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