Year | Value | 2021 | 6.6 | 2020 | 6.6 | 2019 | 6.6 | 2018 | 6.6 | 2017 | 6.6 | 2016 | 6.6 | 2015 | 6.6 | 2014 | 6.6 | 2013 | 6.7 | 2012 | 7.3 | 2011 | 7.3 | 2010 | 7.4 | 2009 | 7 | 2008 | 7 | 2007 | 8 | 2006 | 7.5 | 2005 | 7.6 | 2004 | 8 | 2003 | 8 | 2002 | 12 | 2001 | 12 | 2000 | 12 | 1999 | 12 | 1998 | 12 | 1997 | 12 | 1996 | 12 | 1995 | 12 | 1994 | 12 | 1993 | 12 | 1992 | 12 | 1991 | 12 | 1990 | 20 | 1989 | 20 | 1988 | 30 | 1987 | 30 | 1986 | 40 | 1985 | 50 | 1984 | 60 | 1983 | 60 | 1982 | 60 | 1981 | 70 | 1980 | 80 | 1979 | 80 | 1978 | 80 | 1977 | 80 | 1976 | 80 | 1975 | 80 | 1974 | 90 | 1973 | 110 | 1972 | 110 | 1971 | 100 | 1970 | 120 | 1969 | 120 | 1968 | 120 | 1967 | 130 | 1966 | 130 | 1965 | 130 | 1964 | 130 | 1963 | 130 | 1962 | 140 | 1961 | 140 |
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