Year | Value | 2021 | 58.69 | 2020 | 59.081 | 2019 | 60.186 | 2018 | 59.602 | 2017 | 59.465 | 2016 | 58.875 | 2015 | 58.127 | 2014 | 57.45 | 2013 | 57.104 | 2012 | 56.424 | 2011 | 55.776 | 2010 | 55.193 | 2009 | 54.776 | 2008 | 54.32 | 2007 | 53.862 | 2006 | 53.534 | 2005 | 53.047 | 2004 | 52.724 | 2003 | 52.46 | 2002 | 51.97 | 2001 | 51.561 | 2000 | 51.316 | 1999 | 51.001 | 1998 | 50.973 | 1997 | 51.103 | 1996 | 51.202 | 1995 | 51.597 | 1994 | 51.976 | 1993 | 52.582 | 1992 | 52.964 | 1991 | 53.261 | 1990 | 53.546 | 1989 | 53.699 | 1988 | 53.69 | 1987 | 53.522 | 1986 | 52.975 | 1985 | 52.841 | 1984 | 52.013 | 1983 | 51.571 | 1982 | 50.893 | 1981 | 50.194 | 1980 | 49.62 | 1979 | 49.15 | 1978 | 48.877 | 1977 | 48.604 | 1976 | 48.487 | 1975 | 48.375 | 1974 | 48.271 | 1973 | 47.983 | 1972 | 47.583 | 1971 | 46.956 | 1970 | 46.358 | 1969 | 45.556 | 1968 | 44.72 | 1967 | 43.946 | 1966 | 43.216 | 1965 | 42.668 | 1964 | 42.1 | 1963 | 41.663 | 1962 | 41.239 | 1961 | 29.975 | 1960 | 29.46 |
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