Year | Value | 2022 | 18.698 | 2021 | 19.006 | 2020 | 19.309 | 2019 | 19.607 | 2018 | 19.898 | 2017 | 20.183 | 2016 | 20.46 | 2015 | 20.73 | 2014 | 20.991 | 2013 | 21.244 | 2012 | 21.488 | 2011 | 21.723 | 2010 | 21.948 | 2009 | 22.163 | 2008 | 22.368 | 2007 | 22.563 | 2006 | 22.747 | 2005 | 22.92 | 2004 | 23.081 | 2003 | 23.232 | 2002 | 23.371 | 2001 | 23.498 | 2000 | 23.613 | 1999 | 23.716 | 1998 | 23.807 | 1997 | 23.886 | 1996 | 23.952 | 1995 | 24.006 | 1994 | 24.06 | 1993 | 24.114 | 1992 | 24.168 | 1991 | 24.223 | 1990 | 24.277 | 1989 | 24.331 | 1988 | 24.386 | 1987 | 24.44 | 1986 | 24.495 | 1985 | 24.55 | 1984 | 24.7 | 1983 | 25.945 | 1982 | 27.227 | 1981 | 28.549 | 1980 | 29.906 | 1979 | 31.304 | 1978 | 32.735 | 1977 | 34.198 | 1976 | 35.69 | 1975 | 37.215 | 1974 | 38.763 | 1973 | 40.472 | 1972 | 43.708 | 1971 | 47.008 | 1970 | 50.329 | 1969 | 53.648 | 1968 | 56.93 | 1967 | 60.161 | 1966 | 63.302 | 1965 | 66.334 | 1964 | 69.076 | 1963 | 70.002 | 1962 | 70.911 | 1961 | 71.803 | 1960 | 72.677 |
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