| Year | Value | | 2022 | 6,130 | | 2021 | 6,004 | | 2020 | 6,325 | | 2019 | 6,883 | | 2018 | 7,358 | | 2017 | 7,746 | | 2016 | 7,986 | | 2015 | 8,025 | | 2014 | 7,906 | | 2013 | 7,677 | | 2012 | 7,413 | | 2011 | 7,208 | | 2010 | 7,032 | | 2009 | 6,857 | | 2008 | 6,720 | | 2007 | 6,578 | | 2006 | 6,314 | | 2005 | 5,892 | | 2004 | 5,353 | | 2003 | 4,764 | | 2002 | 4,208 | | 2001 | 3,783 | | 2000 | 3,491 | | 1999 | 3,318 | | 1998 | 3,213 | | 1997 | 3,154 | | 1996 | 3,173 | | 1995 | 3,335 | | 1994 | 3,644 | | 1993 | 4,040 | | 1992 | 4,447 | | 1991 | 4,762 | | 1990 | 4,896 | | 1989 | 4,856 | | 1988 | 4,719 | | 1987 | 4,551 | | 1986 | 4,380 | | 1985 | 4,197 | | 1984 | 3,992 | | 1983 | 3,777 | | 1982 | 3,559 | | 1981 | 3,365 | | 1980 | 3,251 | | 1979 | 3,232 | | 1978 | 3,277 | | 1977 | 3,338 | | 1976 | 3,373 | | 1975 | 3,351 | | 1974 | 3,259 | | 1973 | 3,119 | | 1972 | 2,962 | | 1971 | 2,824 | | 1970 | 2,727 | | 1969 | 2,690 | | 1968 | 2,712 | | 1967 | 2,776 | | 1966 | 2,845 | | 1965 | 2,883 | | 1964 | 2,871 | | 1963 | 2,810 | | 1962 | 2,709 | | 1961 | 2,597 | | 1960 | 2,509 |
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