Year | Value | 2021 | 30.544 | 2020 | 31.252 | 2019 | 31.778 | 2018 | 32.305 | 2017 | 32.713 | 2016 | 33.348 | 2015 | 33.933 | 2014 | 34.428 | 2013 | 34.794 | 2012 | 35.125 | 2011 | 35.49 | 2010 | 35.791 | 2009 | 36.2 | 2008 | 36.722 | 2007 | 37.177 | 2006 | 37.776 | 2005 | 37.917 | 2004 | 38.214 | 2003 | 38.546 | 2002 | 38.654 | 2001 | 39.236 | 2000 | 40.24 | 1999 | 41.105 | 1998 | 41.478 | 1997 | 42.498 | 1996 | 43.273 | 1995 | 46.071 | 1994 | 47.452 | 1993 | 48.668 | 1992 | 49.388 | 1991 | 50.021 | 1990 | 50.636 | 1989 | 51.199 | 1988 | 51.882 | 1987 | 52.377 | 1986 | 52.834 | 1985 | 53.244 | 1984 | 53.537 | 1983 | 53.995 | 1982 | 54.209 | 1981 | 54.372 | 1980 | 54.635 | 1979 | 54.735 | 1978 | 54.198 | 1977 | 54.501 | 1976 | 54.505 | 1975 | 54.637 | 1974 | 54.486 | 1973 | 54.674 | 1972 | 55.02 | 1971 | 55.067 | 1970 | 55.138 | 1969 | 55.168 | 1968 | 55.527 | 1967 | 55.724 | 1966 | 55.646 | 1965 | 55.422 | 1964 | 55.318 | 1963 | 54.943 | 1962 | 54.784 | 1961 | 54.704 | 1960 | 54.408 |
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