Year | Value | 2021 | 37.117 | 2020 | 37.467 | 2019 | 37.849 | 2018 | 38.248 | 2017 | 38.689 | 2016 | 39.128 | 2015 | 39.51 | 2014 | 40.069 | 2013 | 40.603 | 2012 | 41.241 | 2011 | 41.798 | 2010 | 42.094 | 2009 | 42.419 | 2008 | 42.681 | 2007 | 42.721 | 2006 | 42.884 | 2005 | 43.075 | 2004 | 43.151 | 2003 | 43.408 | 2002 | 43.563 | 2001 | 43.563 | 2000 | 43.5 | 1999 | 43.249 | 1998 | 42.87 | 1997 | 43.154 | 1996 | 43.515 | 1995 | 43.744 | 1994 | 43.809 | 1993 | 43.745 | 1992 | 43.655 | 1991 | 43.671 | 1990 | 43.791 | 1989 | 44 | 1988 | 43.873 | 1987 | 44.115 | 1986 | 44.562 | 1985 | 45.189 | 1984 | 45.824 | 1983 | 46.516 | 1982 | 46.705 | 1981 | 47.069 | 1980 | 47.476 | 1979 | 47.881 | 1978 | 48.223 | 1977 | 48.133 | 1976 | 48.051 | 1975 | 48.079 | 1974 | 47.787 | 1973 | 47.289 | 1972 | 47.099 | 1971 | 46.971 | 1970 | 46.685 | 1969 | 46.598 | 1968 | 46.566 | 1967 | 46.527 | 1966 | 46.514 | 1965 | 46.467 | 1964 | 46.463 | 1963 | 46.421 | 1962 | 46.426 | 1961 | 46.243 | 1960 | 46.107 |
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