| Year | Value | | 2022 | 17,499 | | 2021 | 17,110 | | 2020 | 16,814 | | 2019 | 16,533 | | 2018 | 16,226 | | 2017 | 15,877 | | 2016 | 15,507 | | 2015 | 15,120 | | 2014 | 14,693 | | 2013 | 14,238 | | 2012 | 13,762 | | 2011 | 13,255 | | 2010 | 12,705 | | 2009 | 12,102 | | 2008 | 11,433 | | 2007 | 10,703 | | 2006 | 9,961 | | 2005 | 9,273 | | 2004 | 8,697 | | 2003 | 8,351 | | 2002 | 8,314 | | 2001 | 8,360 | | 2000 | 8,232 | | 1999 | 7,860 | | 1998 | 7,413 | | 1997 | 7,095 | | 1996 | 6,908 | | 1995 | 6,820 | | 1994 | 6,861 | | 1993 | 7,020 | | 1992 | 7,186 | | 1991 | 7,332 | | 1990 | 7,458 | | 1989 | 7,552 | | 1988 | 7,623 | | 1987 | 7,669 | | 1986 | 7,685 | | 1985 | 7,662 | | 1984 | 7,598 | | 1983 | 7,493 | | 1982 | 7,354 | | 1981 | 7,190 | | 1980 | 6,988 | | 1979 | 6,734 | | 1978 | 6,460 | | 1977 | 6,200 | | 1976 | 5,959 | | 1975 | 5,741 | | 1974 | 5,542 | | 1973 | 5,362 | | 1972 | 5,203 | | 1971 | 5,065 | | 1970 | 4,946 | | 1969 | 4,844 | | 1968 | 4,758 | | 1967 | 4,693 | | 1966 | 4,643 | | 1965 | 4,594 | | 1964 | 4,539 | | 1963 | 4,479 | | 1962 | 4,414 | | 1961 | 4,346 | | 1960 | 4,275 |
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