| Year | Value | | 2022 | 6,205 | | 2021 | 6,368 | | 2020 | 6,585 | | 2019 | 6,815 | | 2018 | 7,023 | | 2017 | 7,229 | | 2016 | 7,442 | | 2015 | 7,636 | | 2014 | 7,802 | | 2013 | 7,954 | | 2012 | 8,068 | | 2011 | 8,089 | | 2010 | 8,003 | | 2009 | 7,901 | | 2008 | 7,856 | | 2007 | 7,852 | | 2006 | 7,889 | | 2005 | 7,983 | | 2004 | 8,133 | | 2003 | 8,311 | | 2002 | 8,463 | | 2001 | 8,510 | | 2000 | 8,421 | | 1999 | 8,264 | | 1998 | 8,139 | | 1997 | 8,082 | | 1996 | 8,090 | | 1995 | 8,131 | | 1994 | 8,118 | | 1993 | 8,011 | | 1992 | 7,848 | | 1991 | 7,662 | | 1990 | 7,482 | | 1989 | 7,378 | | 1988 | 7,367 | | 1987 | 7,392 | | 1986 | 7,438 | | 1985 | 7,488 | | 1984 | 7,523 | | 1983 | 7,518 | | 1982 | 7,453 | | 1981 | 7,341 | | 1980 | 7,221 | | 1979 | 7,108 | | 1978 | 6,988 | | 1977 | 6,838 | | 1976 | 6,648 | | 1975 | 6,426 | | 1974 | 6,198 | | 1973 | 5,967 | | 1972 | 5,734 | | 1971 | 5,513 | | 1970 | 5,302 | | 1969 | 5,107 | | 1968 | 4,943 | | 1967 | 4,808 | | 1966 | 4,698 | | 1965 | 4,614 | | 1964 | 4,555 | | 1963 | 4,515 | | 1962 | 4,488 | | 1961 | 4,473 | | 1960 | 4,462 |
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