Year | Value | 2021 | 11.926 | 2020 | 12.621 | 2019 | 13.198 | 2018 | 13.818 | 2017 | 14.506 | 2016 | 15.181 | 2015 | 15.791 | 2014 | 15.953 | 2013 | 15.862 | 2012 | 15.955 | 2011 | 15.759 | 2010 | 15.845 | 2009 | 16.089 | 2008 | 16.732 | 2007 | 17.526 | 2006 | 18.705 | 2005 | 19.911 | 2004 | 20.648 | 2003 | 20.869 | 2002 | 20.471 | 2001 | 20.129 | 2000 | 20.739 | 1999 | 21.261 | 1998 | 21.288 | 1997 | 21.523 | 1996 | 21.915 | 1995 | 22.691 | 1994 | 23.625 | 1993 | 24.792 | 1992 | 25.67 | 1991 | 26.361 | 1990 | 27.362 | 1989 | 28.247 | 1988 | 28.393 | 1987 | 28.955 | 1986 | 29.421 | 1985 | 29.45 | 1984 | 29.071 | 1983 | 29.024 | 1982 | 28.973 | 1981 | 29.08 | 1980 | 29.768 | 1979 | 30.448 | 1978 | 31.051 | 1977 | 31.701 | 1976 | 32.305 | 1975 | 32.968 | 1974 | 33.705 | 1973 | 34.598 | 1972 | 35.563 | 1971 | 36.677 | 1970 | 37.712 | 1969 | 38.732 | 1968 | 39.944 | 1967 | 41.252 | 1966 | 42.547 | 1965 | 43.772 | 1964 | 44.646 | 1963 | 45.18 | 1962 | 45.823 | 1961 | 46.396 | 1960 | 46.9 |
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