Year | Value | 2021 | 20.777 | 2020 | 20.837 | 2019 | 21.059 | 2018 | 21.2 | 2017 | 21.451 | 2016 | 21.714 | 2015 | 21.855 | 2014 | 22.266 | 2013 | 22.652 | 2012 | 22.975 | 2011 | 23.405 | 2010 | 23.696 | 2009 | 24.284 | 2008 | 24.819 | 2007 | 25.431 | 2006 | 26.139 | 2005 | 26.962 | 2004 | 27.647 | 2003 | 28.327 | 2002 | 29.213 | 2001 | 30.357 | 2000 | 31.423 | 1999 | 31.867 | 1998 | 32.257 | 1997 | 32.386 | 1996 | 32.385 | 1995 | 32.167 | 1994 | 32.525 | 1993 | 33.046 | 1992 | 33.427 | 1991 | 33.747 | 1990 | 34.149 | 1989 | 34.694 | 1988 | 35.382 | 1987 | 35.939 | 1986 | 36.575 | 1985 | 37.314 | 1984 | 38.034 | 1983 | 38.651 | 1982 | 39.196 | 1981 | 39.618 | 1980 | 39.97 | 1979 | 40.504 | 1978 | 40.745 | 1977 | 40.753 | 1976 | 40.767 | 1975 | 40.781 | 1974 | 41.283 | 1973 | 41.785 | 1972 | 42.33 | 1971 | 42.84 | 1970 | 42.954 | 1969 | 42.796 | 1968 | 42.823 | 1967 | 42.84 | 1966 | 42.86 | 1965 | 42.865 | 1964 | 43.173 | 1963 | 43.361 | 1962 | 43.488 | 1961 | 43.7 | 1960 | 43.905 |
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