Year | Value | 2021 | 29.398 | 2020 | 29.896 | 2019 | 30.4 | 2018 | 30.859 | 2017 | 31.33 | 2016 | 31.756 | 2015 | 32.147 | 2014 | 32.594 | 2013 | 32.996 | 2012 | 33.408 | 2011 | 33.841 | 2010 | 33.924 | 2009 | 33.944 | 2008 | 33.938 | 2007 | 34.07 | 2006 | 34.293 | 2005 | 34.515 | 2004 | 34.561 | 2003 | 34.526 | 2002 | 35.017 | 2001 | 35.505 | 2000 | 35.895 | 1999 | 36.507 | 1998 | 37.046 | 1997 | 37.505 | 1996 | 38.003 | 1995 | 38.407 | 1994 | 38.89 | 1993 | 39.804 | 1992 | 40.632 | 1991 | 41.352 | 1990 | 41.987 | 1989 | 42.615 | 1988 | 43.171 | 1987 | 43.626 | 1986 | 44.096 | 1985 | 44.48 | 1984 | 44.878 | 1983 | 45.185 | 1982 | 45.448 | 1981 | 45.569 | 1980 | 45.609 | 1979 | 45.709 | 1978 | 45.609 | 1977 | 45.577 | 1976 | 45.62 | 1975 | 45.575 | 1974 | 45.584 | 1973 | 45.587 | 1972 | 45.544 | 1971 | 45.576 | 1970 | 45.569 | 1969 | 45.708 | 1968 | 45.909 | 1967 | 46.105 | 1966 | 46.351 | 1965 | 46.632 | 1964 | 46.923 | 1963 | 47.175 | 1962 | 47.428 | 1961 | 47.62 | 1960 | 47.731 |
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