Year | Value | 2021 | 57.595 | 2020 | 58.113 | 2019 | 58.544 | 2018 | 58.326 | 2017 | 57.926 | 2016 | 57.761 | 2015 | 56.874 | 2014 | 56.434 | 2013 | 56.489 | 2012 | 55.995 | 2011 | 55.851 | 2010 | 55.518 | 2009 | 55.313 | 2008 | 54.97 | 2007 | 54.587 | 2006 | 54.302 | 2005 | 53.919 | 2004 | 53.535 | 2003 | 53.23 | 2002 | 52.878 | 2001 | 52.174 | 2000 | 52.096 | 1999 | 51.921 | 1998 | 51.578 | 1997 | 50.644 | 1996 | 49.88 | 1995 | 49.127 | 1994 | 48.358 | 1993 | 48.123 | 1992 | 47.523 | 1991 | 46.853 | 1990 | 46.449 | 1989 | 46.156 | 1988 | 45.772 | 1987 | 45.429 | 1986 | 44.876 | 1985 | 44.334 | 1984 | 43.756 | 1983 | 43.061 | 1982 | 42.608 | 1981 | 41.883 | 1980 | 41.431 | 1979 | 40.957 | 1978 | 40.489 | 1977 | 40.034 | 1976 | 39.735 | 1975 | 39.272 | 1974 | 38.856 | 1973 | 38.616 | 1972 | 38.304 | 1971 | 37.964 | 1970 | 37.655 | 1969 | 37.374 | 1968 | 37.202 | 1967 | 36.829 | 1966 | 36.581 | 1965 | 36.276 | 1964 | 36.039 | 1963 | 35.837 | 1962 | 35.651 | 1961 | 35.501 | 1960 | 35.26 |
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