Year | Value | 2021 | 29.785 | 2020 | 30.223 | 2019 | 30.762 | 2018 | 31.219 | 2017 | 31.743 | 2016 | 32.379 | 2015 | 32.928 | 2014 | 33.477 | 2013 | 33.585 | 2012 | 33.619 | 2011 | 33.633 | 2010 | 33.641 | 2009 | 33.562 | 2008 | 33.663 | 2007 | 33.828 | 2006 | 34.007 | 2005 | 33.884 | 2004 | 34.117 | 2003 | 34.397 | 2002 | 34.661 | 2001 | 34.989 | 2000 | 35.271 | 1999 | 35.629 | 1998 | 35.926 | 1997 | 36.194 | 1996 | 36.753 | 1995 | 37.225 | 1994 | 37.316 | 1993 | 37.362 | 1992 | 37.455 | 1991 | 37.73 | 1990 | 38.064 | 1989 | 38.396 | 1988 | 38.69 | 1987 | 38.967 | 1986 | 39.367 | 1985 | 39.591 | 1984 | 39.802 | 1983 | 40.058 | 1982 | 40.31 | 1981 | 40.61 | 1980 | 40.941 | 1979 | 41.216 | 1978 | 41.537 | 1977 | 41.838 | 1976 | 42.077 | 1975 | 42.374 | 1974 | 42.756 | 1973 | 42.682 | 1972 | 42.671 | 1971 | 42.757 | 1970 | 42.844 | 1969 | 42.808 | 1968 | 42.763 | 1967 | 43.151 | 1966 | 43.396 | 1965 | 43.657 | 1964 | 43.935 | 1963 | 44.12 | 1962 | 44.311 | 1961 | 44.417 | 1960 | 44.495 |
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