| Year | Value | | 2021 | 7,555.1 | | 2020 | 7,555.1 | | 2019 | 7,567.1 | | 2018 | 7,631.7 | | 2017 | 7,707 | | 2016 | 7,752.1 | | 2015 | 7,817.2 | | 2014 | 7,718 | | 2013 | 7,635 | | 2012 | 7,582 | | 2011 | 7,504 | | 2010 | 7,416 | | 2009 | 7,297 | | 2008 | 7,339 | | 2007 | 7,382 | | 2006 | 7,426 | | 2005 | 7,432 | | 2004 | 7,410 | | 2003 | 7,468 | | 2002 | 7,486 | | 2001 | 7,524 | | 2000 | 7,555 | | 1999 | 7,631 | | 1998 | 7,661 | | 1997 | 7,699 | | 1996 | 7,767 | | 1995 | 7,805 | | 1994 | 7,793 | | 1993 | 7,841 | | 1992 | 7,899 | | 1991 | 7,927 | | 1990 | 7,962 | | 1989 | 7,784 | | 1988 | 7,842 | | 1987 | 7,629 | | 1986 | 7,486 | | 1985 | 7,372 | | 1984 | 7,202 | | 1983 | 7,068 | | 1982 | 6,942 | | 1981 | 6,802 | | 1980 | 6,642 | | 1979 | 6,577 | | 1978 | 6,472 | | 1977 | 6,362 | | 1976 | 6,222 | | 1975 | 6,042 | | 1974 | 5,922 | | 1973 | 5,862 | | 1972 | 5,812 | | 1971 | 5,712 | | 1970 | 5,707 | | 1969 | 5,642 | | 1968 | 5,602 | | 1967 | 5,612 | | 1966 | 5,682 | | 1965 | 5,672 | | 1964 | 5,581 | | 1963 | 5,581 | | 1962 | 5,521 | | 1961 | 5,501 |
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