| Year | Value | | 2022 | 9,173 | | 2021 | 9,080 | | 2020 | 8,993 | | 2019 | 8,984 | | 2018 | 9,031 | | 2017 | 9,060 | | 2016 | 9,064 | | 2015 | 8,996 | | 2014 | 8,831 | | 2013 | 8,618 | | 2012 | 8,388 | | 2011 | 8,122 | | 2010 | 7,888 | | 2009 | 7,746 | | 2008 | 7,652 | | 2007 | 7,597 | | 2006 | 7,607 | | 2005 | 7,702 | | 2004 | 7,848 | | 2003 | 8,013 | | 2002 | 8,188 | | 2001 | 8,429 | | 2000 | 8,719 | | 1999 | 8,985 | | 1998 | 9,220 | | 1997 | 9,402 | | 1996 | 9,507 | | 1995 | 9,529 | | 1994 | 9,490 | | 1993 | 9,412 | | 1992 | 9,322 | | 1991 | 9,287 | | 1990 | 9,328 | | 1989 | 9,360 | | 1988 | 9,309 | | 1987 | 9,156 | | 1986 | 8,990 | | 1985 | 8,896 | | 1984 | 8,828 | | 1983 | 8,725 | | 1982 | 8,550 | | 1981 | 8,345 | | 1980 | 8,144 | | 1979 | 7,896 | | 1978 | 7,565 | | 1977 | 7,156 | | 1976 | 6,832 | | 1975 | 6,688 | | 1974 | 6,609 | | 1973 | 6,454 | | 1972 | 6,205 | | 1971 | 5,944 | | 1970 | 5,692 | | 1969 | 5,469 | | 1968 | 5,261 | | 1967 | 5,088 | | 1966 | 4,960 | | 1965 | 4,851 | | 1964 | 4,778 | | 1963 | 4,729 | | 1962 | 4,676 | | 1961 | 4,588 | | 1960 | 4,444 |
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