Year | Value | 2022 | 37.83 | 2021 | 37.934 | 2020 | 38.025 | 2019 | 38.103 | 2018 | 38.166 | 2017 | 38.216 | 2016 | 38.266 | 2015 | 38.317 | 2014 | 38.367 | 2013 | 38.417 | 2012 | 38.541 | 2011 | 39.111 | 2010 | 39.683 | 2009 | 40.258 | 2008 | 40.834 | 2007 | 41.415 | 2006 | 41.998 | 2005 | 42.583 | 2004 | 43.169 | 2003 | 43.758 | 2002 | 44.112 | 2001 | 44.033 | 2000 | 43.953 | 1999 | 43.874 | 1998 | 43.795 | 1997 | 43.715 | 1996 | 43.607 | 1995 | 43.363 | 1994 | 43.119 | 1993 | 42.876 | 1992 | 42.633 | 1991 | 42.39 | 1990 | 42.148 | 1989 | 41.906 | 1988 | 41.69 | 1987 | 41.581 | 1986 | 41.473 | 1985 | 41.365 | 1984 | 41.257 | 1983 | 41.164 | 1982 | 41.108 | 1981 | 41.052 | 1980 | 40.997 | 1979 | 40.941 | 1978 | 40.885 | 1977 | 40.829 | 1976 | 41.24 | 1975 | 41.748 | 1974 | 42.258 | 1973 | 42.769 | 1972 | 43.282 | 1971 | 43.797 | 1970 | 44.838 | 1969 | 46.227 | 1968 | 47.62 | 1967 | 49.021 | 1966 | 50.422 | 1965 | 51.822 | 1964 | 53.217 | 1963 | 54.611 | 1962 | 55.84 | 1961 | 56.783 | 1960 | 57.719 |
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