Year | Value | 2021 | 42.68 | 2020 | 42.175 | 2019 | 41.92 | 2018 | 41.831 | 2017 | 41.602 | 2016 | 41.209 | 2015 | 41.044 | 2014 | 41.921 | 2013 | 42.414 | 2012 | 43.006 | 2011 | 43.223 | 2010 | 43.237 | 2009 | 43.019 | 2008 | 42.925 | 2007 | 42.776 | 2006 | 42.771 | 2005 | 42.633 | 2004 | 42.545 | 2003 | 42.765 | 2002 | 42.635 | 2001 | 42.809 | 2000 | 43.259 | 1999 | 43.397 | 1998 | 43.514 | 1997 | 43.796 | 1996 | 44.266 | 1995 | 44.482 | 1994 | 44.539 | 1993 | 44.926 | 1992 | 45.407 | 1991 | 45.98 | 1990 | 46.292 | 1989 | 46.527 | 1988 | 46.509 | 1987 | 46.531 | 1986 | 46.169 | 1985 | 45.89 | 1984 | 45.548 | 1983 | 45.221 | 1982 | 44.931 | 1981 | 44.598 | 1980 | 44.08 | 1979 | 43.588 | 1978 | 42.977 | 1977 | 42.421 | 1976 | 41.995 | 1975 | 41.899 | 1974 | 42.285 | 1973 | 42.618 | 1972 | 43.086 | 1971 | 43.501 | 1970 | 43.73 | 1969 | 44.076 | 1968 | 44.257 | 1967 | 43.987 | 1966 | 43.773 | 1965 | 43.448 | 1964 | 43.251 | 1963 | 43.043 | 1962 | 43.015 | 1961 | 42.948 | 1960 | 42.934 |
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