Year | Value | 2021 | 9.461 | 2020 | 6.95 | 2019 | 6.974 | 2018 | 6.922 | 2017 | 6.308 | 2016 | 6.783 | 2015 | 7.435 | 2014 | 7.927 | 2013 | 8.157 | 2012 | 8.671 | 2011 | 8.738 | 2010 | 8.93 | 2009 | 9.719 | 2008 | 10.253 | 2007 | 10.935 | 2006 | 11.883 | 2005 | 12.568 | 2004 | 13.073 | 2003 | 13.409 | 2002 | 13.533 | 2001 | 13.424 | 2000 | 13.128 | 1999 | 12.633 | 1998 | 12.081 | 1997 | 11.508 | 1996 | 10.988 | 1995 | 10.596 | 1994 | 10.025 | 1993 | 9.282 | 1992 | 8.933 | 1991 | 8.423 | 1990 | 7.986 | 1989 | 7.652 | 1988 | 7.6 | 1987 | 7.345 | 1986 | 7.366 | 1985 | 7.468 | 1984 | 7.65 | 1983 | 7.904 | 1982 | 8.208 | 1981 | 8.534 | 1980 | 8.881 | 1979 | 9.231 | 1978 | 9.6 | 1977 | 9.997 | 1976 | 10.431 | 1975 | 10.857 | 1974 | 11.291 | 1973 | 11.739 | 1972 | 12.209 | 1971 | 12.656 | 1970 | 13.033 | 1969 | 13.375 | 1968 | 13.715 | 1967 | 14.032 | 1966 | 14.343 | 1965 | 14.635 | 1964 | 15.031 | 1963 | 15.418 | 1962 | 15.839 | 1961 | 16.301 | 1960 | 16.77 |
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