| Year | Value | | 2022 | 6,469 | | 2021 | 6,573 | | 2020 | 6,647 | | 2019 | 6,628 | | 2018 | 6,554 | | 2017 | 6,480 | | 2016 | 6,403 | | 2015 | 6,307 | | 2014 | 6,186 | | 2013 | 6,043 | | 2012 | 5,883 | | 2011 | 5,719 | | 2010 | 5,562 | | 2009 | 5,414 | | 2008 | 5,275 | | 2007 | 5,142 | | 2006 | 5,013 | | 2005 | 4,896 | | 2004 | 4,789 | | 2003 | 4,688 | | 2002 | 4,596 | | 2001 | 4,510 | | 2000 | 4,423 | | 1999 | 4,336 | | 1998 | 4,253 | | 1997 | 4,173 | | 1996 | 4,095 | | 1995 | 4,024 | | 1994 | 3,959 | | 1993 | 3,895 | | 1992 | 3,831 | | 1991 | 3,767 | | 1990 | 3,705 | | 1989 | 3,642 | | 1988 | 3,578 | | 1987 | 3,514 | | 1986 | 3,454 | | 1985 | 3,395 | | 1984 | 3,336 | | 1983 | 3,276 | | 1982 | 3,220 | | 1981 | 3,164 | | 1980 | 3,109 | | 1979 | 3,053 | | 1978 | 2,998 | | 1977 | 2,942 | | 1976 | 2,886 | | 1975 | 2,831 | | 1974 | 2,776 | | 1973 | 2,723 | | 1972 | 2,669 | | 1971 | 2,617 | | 1970 | 2,563 | | 1969 | 2,499 | | 1968 | 2,440 | | 1967 | 2,388 | | 1966 | 2,335 | | 1965 | 2,280 | | 1964 | 2,225 | | 1963 | 2,169 | | 1962 | 2,114 | | 1961 | 2,056 | | 1960 | 1,998 |
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