| Year | Value | | 2022 | 12,509 | | 2021 | 12,275 | | 2020 | 12,137 | | 2019 | 12,051 | | 2018 | 11,845 | | 2017 | 11,475 | | 2016 | 11,158 | | 2015 | 10,917 | | 2014 | 10,656 | | 2013 | 10,512 | | 2012 | 10,605 | | 2011 | 10,702 | | 2010 | 10,619 | | 2009 | 10,583 | | 2008 | 10,480 | | 2007 | 10,174 | | 2006 | 10,082 | | 2005 | 10,237 | | 2004 | 10,449 | | 2003 | 10,705 | | 2002 | 10,873 | | 2001 | 10,811 | | 2000 | 10,708 | | 1999 | 10,628 | | 1998 | 10,496 | | 1997 | 10,374 | | 1996 | 10,305 | | 1995 | 10,257 | | 1994 | 10,125 | | 1993 | 9,922 | | 1992 | 9,668 | | 1991 | 9,409 | | 1990 | 9,156 | | 1989 | 8,922 | | 1988 | 8,723 | | 1987 | 8,505 | | 1986 | 8,191 | | 1985 | 7,879 | | 1984 | 7,637 | | 1983 | 7,342 | | 1982 | 7,041 | | 1981 | 6,766 | | 1980 | 6,460 | | 1979 | 6,144 | | 1978 | 5,822 | | 1977 | 5,522 | | 1976 | 5,376 | | 1975 | 5,366 | | 1974 | 5,401 | | 1973 | 5,453 | | 1972 | 5,507 | | 1971 | 5,553 | | 1970 | 5,664 | | 1969 | 5,794 | | 1968 | 5,830 | | 1967 | 5,821 | | 1966 | 5,798 | | 1965 | 5,661 | | 1964 | 5,477 | | 1963 | 5,411 | | 1962 | 5,386 | | 1961 | 5,369 | | 1960 | 5,360 |
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