Year | Value | 2022 | 16.336 | 2021 | 16.677 | 2020 | 17.026 | 2019 | 17.384 | 2018 | 17.752 | 2017 | 18.129 | 2016 | 18.515 | 2015 | 18.909 | 2014 | 19.308 | 2013 | 19.714 | 2012 | 20.126 | 2011 | 20.545 | 2010 | 20.898 | 2009 | 21.185 | 2008 | 21.474 | 2007 | 21.766 | 2006 | 22.05 | 2005 | 22.325 | 2004 | 22.601 | 2003 | 22.916 | 2002 | 23.267 | 2001 | 23.622 | 2000 | 23.98 | 1999 | 24.431 | 1998 | 24.973 | 1997 | 25.524 | 1996 | 25.938 | 1995 | 26.213 | 1994 | 26.547 | 1993 | 26.939 | 1992 | 27.335 | 1991 | 27.735 | 1990 | 28.044 | 1989 | 28.172 | 1988 | 28.301 | 1987 | 28.43 | 1986 | 28.56 | 1985 | 28.69 | 1984 | 28.82 | 1983 | 28.951 | 1982 | 29.082 | 1981 | 29.213 | 1980 | 29.455 | 1979 | 29.919 | 1978 | 30.386 | 1977 | 30.858 | 1976 | 31.333 | 1975 | 31.813 | 1974 | 32.297 | 1973 | 32.784 | 1972 | 33.275 | 1971 | 33.77 | 1970 | 34.604 | 1969 | 36.119 | 1968 | 37.66 | 1967 | 39.23 | 1966 | 40.821 | 1965 | 42.432 | 1964 | 44.056 | 1963 | 45.698 | 1962 | 47.347 | 1961 | 49.002 | 1960 | 50.08 |
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