Year | Value | 2021 | 14.5 | 2020 | 14.35 | 2019 | 14.2 | 2018 | 14.05 | 2017 | 13.9 | 2016 | 13.75 | 2015 | 13.6 | 2014 | 13.45 | 2013 | 13.3 | 2012 | 13.15 | 2011 | 13 | 2010 | 12.85 | 2009 | 12.7 | 2008 | 12.55 | 2007 | 12.4 | 2006 | 12.25 | 2005 | 12.1 | 2004 | 11.95 | 2003 | 11.8 | 2002 | 11.65 | 2001 | 11.5 | 2000 | 11.35 | 1999 | 11.18 | 1998 | 11.01 | 1997 | 10.84 | 1996 | 10.67 | 1995 | 10.5 | 1994 | 10.33 | 1993 | 10.16 | 1992 | 9.99 | 1991 | 9.82 | 1990 | 9.65 | 1989 | 9.65 | 1988 | 9.65 | 1987 | 9.65 | 1986 | 9.65 | 1985 | 9.65 | 1984 | 9.65 | 1983 | 9.65 | 1982 | 9.65 | 1981 | 9.65 | 1980 | 9.65 | 1979 | 9.65 | 1978 | 9.65 | 1977 | 9.65 | 1976 | 9.65 | 1975 | 9.65 | 1974 | 9.65 | 1973 | 9.65 | 1972 | 9.65 | 1971 | 9.65 | 1970 | 9.65 | 1969 | 9.65 | 1968 | 9.65 | 1967 | 9.65 | 1966 | 9.65 | 1965 | 9.65 | 1964 | 9.65 | 1963 | 9.65 | 1962 | 9.65 | 1961 | 9.65 |
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