Year | Value | 2023 | 7.196 | 2022 | 7.3 | 2021 | 7.932 | 2020 | 7.662 | 2019 | 7.644 | 2018 | 7.733 | 2017 | 7.828 | 2016 | 7.943 | 2015 | 8.063 | 2014 | 8.198 | 2013 | 8.323 | 2012 | 8.471 | 2011 | 8.596 | 2010 | 8.706 | 2009 | 8.865 | 2008 | 8.985 | 2007 | 9.186 | 2006 | 9.293 | 2005 | 9.456 | 2004 | 9.623 | 2003 | 9.834 | 2002 | 10.125 | 2001 | 10.24 | 2000 | 10.606 | 1999 | 10.705 | 1998 | 11.06 | 1997 | 11.149 | 1996 | 11.296 | 1995 | 11.535 | 1994 | 11.819 | 1993 | 12.155 | 1992 | 12.478 | 1991 | 12.758 | 1990 | 13.104 | 1989 | 13.546 | 1988 | 13.837 | 1987 | 14.254 | 1986 | 14.564 | 1985 | 14.946 | 1984 | 15.313 | 1983 | 15.794 | 1982 | 16.086 | 1981 | 16.475 | 1980 | 16.917 | 1979 | 17.333 | 1978 | 17.636 | 1977 | 17.996 | 1976 | 18.353 | 1975 | 19.533 |
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