| Year | Value | | 2022 | 10,380 | | 2021 | 10,304 | | 2020 | 10,197 | | 2019 | 10,000 | | 2018 | 9,723 | | 2017 | 9,423 | | 2016 | 9,113 | | 2015 | 8,807 | | 2014 | 8,515 | | 2013 | 8,244 | | 2012 | 7,998 | | 2011 | 7,784 | | 2010 | 7,609 | | 2009 | 7,472 | | 2008 | 7,371 | | 2007 | 7,305 | | 2006 | 7,275 | | 2005 | 7,281 | | 2004 | 7,317 | | 2003 | 7,382 | | 2002 | 7,468 | | 2001 | 7,571 | | 2000 | 7,689 | | 1999 | 7,822 | | 1998 | 7,967 | | 1997 | 8,108 | | 1996 | 8,229 | | 1995 | 8,328 | | 1994 | 8,396 | | 1993 | 8,425 | | 1992 | 8,451 | | 1991 | 8,528 | | 1990 | 8,537 | | 1989 | 8,451 | | 1988 | 8,379 | | 1987 | 8,319 | | 1986 | 8,263 | | 1985 | 8,202 | | 1984 | 8,125 | | 1983 | 8,020 | | 1982 | 7,889 | | 1981 | 7,744 | | 1980 | 7,598 | | 1979 | 7,584 | | 1978 | 7,610 | | 1977 | 7,456 | | 1976 | 7,118 | | 1975 | 6,593 | | 1974 | 5,894 | | 1973 | 5,320 | | 1972 | 4,972 | | 1971 | 4,708 | | 1970 | 4,532 | | 1969 | 4,442 | | 1968 | 4,453 | | 1967 | 4,520 | | 1966 | 4,605 | | 1965 | 4,664 | | 1964 | 4,691 | | 1963 | 4,631 | | 1962 | 4,459 | | 1961 | 4,282 | | 1960 | 4,153 |
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