Year | Value | 2021 | 3.978 | 2020 | 4.08 | 2019 | 4.192 | 2018 | 4.294 | 2017 | 4.389 | 2016 | 4.466 | 2015 | 4.548 | 2014 | 4.703 | 2013 | 4.873 | 2012 | 5.064 | 2011 | 5.209 | 2010 | 5.327 | 2009 | 5.448 | 2008 | 5.563 | 2007 | 5.643 | 2006 | 5.737 | 2005 | 5.807 | 2004 | 5.919 | 2003 | 6.087 | 2002 | 6.23 | 2001 | 6.305 | 2000 | 6.355 | 1999 | 6.423 | 1998 | 6.495 | 1997 | 6.531 | 1996 | 6.552 | 1995 | 6.555 | 1994 | 6.557 | 1993 | 6.569 | 1992 | 6.555 | 1991 | 6.553 | 1990 | 6.567 | 1989 | 6.571 | 1988 | 6.588 | 1987 | 6.609 | 1986 | 6.597 | 1985 | 6.592 | 1984 | 6.592 | 1983 | 6.573 | 1982 | 6.563 | 1981 | 6.554 | 1980 | 6.562 | 1979 | 6.582 | 1978 | 6.591 | 1977 | 6.568 | 1976 | 6.553 | 1975 | 6.546 | 1974 | 6.534 | 1973 | 6.473 | 1972 | 6.447 | 1971 | 6.429 | 1970 | 6.411 | 1969 | 6.393 | 1968 | 6.385 | 1967 | 6.383 | 1966 | 6.345 | 1965 | 6.311 | 1964 | 6.294 | 1963 | 6.261 | 1962 | 6.222 | 1961 | 6.205 | 1960 | 6.175 |
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