Year | Value | 2021 | 30.498 | 2020 | 31.174 | 2019 | 31.874 | 2018 | 32.667 | 2017 | 33.507 | 2016 | 34.392 | 2015 | 35.229 | 2014 | 36.047 | 2013 | 36.803 | 2012 | 37.458 | 2011 | 38.06 | 2010 | 38.674 | 2009 | 39.163 | 2008 | 39.528 | 2007 | 39.767 | 2006 | 39.873 | 2005 | 39.948 | 2004 | 39.967 | 2003 | 40.047 | 2002 | 40.285 | 2001 | 40.704 | 2000 | 41.319 | 1999 | 41.772 | 1998 | 42.28 | 1997 | 42.793 | 1996 | 43.327 | 1995 | 43.855 | 1994 | 44.412 | 1993 | 44.811 | 1992 | 45.209 | 1991 | 45.625 | 1990 | 46.033 | 1989 | 46.439 | 1988 | 46.758 | 1987 | 46.931 | 1986 | 46.787 | 1985 | 46.259 | 1984 | 45.241 | 1983 | 43.773 | 1982 | 43.63 | 1981 | 43.505 | 1980 | 43.399 | 1979 | 43.22 | 1978 | 43.084 | 1977 | 42.985 | 1976 | 42.88 | 1975 | 42.779 | 1974 | 42.733 | 1973 | 42.69 | 1972 | 42.625 | 1971 | 42.539 | 1970 | 42.365 | 1969 | 42.106 | 1968 | 41.823 | 1967 | 41.503 | 1966 | 41.241 | 1965 | 40.954 | 1964 | 40.752 | 1963 | 40.621 | 1962 | 40.56 | 1961 | 40.556 | 1960 | 40.634 |
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