Year | Value | 2021 | 11.873 | 2020 | 12.152 | 2019 | 12.847 | 2018 | 13.562 | 2017 | 13.926 | 2016 | 14.145 | 2015 | 14.522 | 2014 | 14.852 | 2013 | 15.093 | 2012 | 15.483 | 2011 | 15.772 | 2010 | 16.04 | 2009 | 16.53 | 2008 | 16.899 | 2007 | 16.823 | 2006 | 16.797 | 2005 | 16.99 | 2004 | 17.228 | 2003 | 17.656 | 2002 | 18.12 | 2001 | 19.104 | 2000 | 19.788 | 1999 | 20.301 | 1998 | 20.679 | 1997 | 21.503 | 1996 | 22.058 | 1995 | 22.845 | 1994 | 23.571 | 1993 | 24.287 | 1992 | 24.999 | 1991 | 25.831 | 1990 | 26.734 | 1989 | 27.467 | 1988 | 28.255 | 1987 | 28.961 | 1986 | 29.651 | 1985 | 30.147 | 1984 | 30.241 | 1983 | 30.275 | 1982 | 30.242 | 1981 | 30.212 | 1980 | 30.223 | 1979 | 30.397 | 1978 | 30.106 | 1977 | 29.962 | 1976 | 29.865 | 1975 | 29.778 | 1974 | 29.935 | 1973 | 30.137 | 1972 | 30.748 | 1971 | 31.638 | 1970 | 32.64 | 1969 | 33.837 | 1968 | 34.717 | 1967 | 36.91 | 1966 | 38.532 | 1965 | 40.121 | 1964 | 41.628 | 1963 | 42.961 | 1962 | 44.094 | 1961 | 44.999 | 1960 | 45.636 |
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