Year | Value | 2021 | 58.941 | 2020 | 58.633 | 2019 | 59.664 | 2018 | 59.393 | 2017 | 59.132 | 2016 | 58.731 | 2015 | 58.363 | 2014 | 57.9 | 2013 | 57.357 | 2012 | 57.079 | 2011 | 56.755 | 2010 | 56.382 | 2009 | 55.874 | 2008 | 55.291 | 2007 | 54.941 | 2006 | 54.615 | 2005 | 54.003 | 2004 | 53.538 | 2003 | 52.893 | 2002 | 52.222 | 2001 | 51.284 | 2000 | 50.539 | 1999 | 49.797 | 1998 | 49.164 | 1997 | 48.531 | 1996 | 47.792 | 1995 | 47.816 | 1994 | 47.742 | 1993 | 47.733 | 1992 | 47.496 | 1991 | 47.216 | 1990 | 46.62 | 1989 | 45.877 | 1988 | 45.393 | 1987 | 44.693 | 1986 | 43.977 | 1985 | 43.207 | 1984 | 42.699 | 1983 | 42.142 | 1982 | 41.824 | 1981 | 41.215 | 1980 | 40.751 | 1979 | 39.953 | 1978 | 39.062 | 1977 | 38.106 | 1976 | 37.195 | 1975 | 36.225 | 1974 | 35.426 | 1973 | 34.565 | 1972 | 33.86 | 1971 | 32.937 | 1970 | 32.532 | 1969 | 32.045 | 1968 | 31.631 | 1967 | 31.212 | 1966 | 30.871 | 1965 | 30.623 | 1964 | 30.418 | 1963 | 30.154 | 1962 | 29.939 | 1961 | 29.83 | 1960 | 29.754 |
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