Year | Value | 2021 | 53.246 | 2020 | 53.967 | 2019 | 55.122 | 2018 | 54.283 | 2017 | 53.577 | 2016 | 52.887 | 2015 | 52.855 | 2014 | 52.267 | 2013 | 51.97 | 2012 | 51.248 | 2011 | 49.625 | 2010 | 48.669 | 2009 | 50.298 | 2008 | 49.456 | 2007 | 48.88 | 2006 | 49.022 | 2005 | 49.176 | 2004 | 49.034 | 2003 | 49.147 | 2002 | 49.334 | 2001 | 49.339 | 2000 | 49.272 | 1999 | 49.093 | 1998 | 49.247 | 1997 | 48.779 | 1996 | 48.946 | 1995 | 49.092 | 1994 | 48.885 | 1993 | 49.196 | 1992 | 26.114 | 1991 | 24.904 | 1990 | 43.572 | 1989 | 43.209 | 1988 | 39.87 | 1987 | 47.525 | 1986 | 47.014 | 1985 | 46.922 | 1984 | 47.078 | 1983 | 46.782 | 1982 | 46.443 | 1981 | 46.283 | 1980 | 46.105 | 1979 | 45.92 | 1978 | 45.43 | 1977 | 45.529 | 1976 | 43.216 | 1975 | 42.832 | 1974 | 42.471 | 1973 | 44.738 | 1972 | 44.547 | 1971 | 44.353 | 1970 | 44.164 | 1969 | 43.975 | 1968 | 43.778 | 1967 | 43.575 | 1966 | 43.364 | 1965 | 43.148 | 1964 | 42.905 | 1963 | 42.704 | 1962 | 42.483 | 1961 | 42.18 | 1960 | 42.071 |
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