| Year | Value | | 2022 | 7,040 | | 2021 | 7,130 | | 2020 | 7,056 | | 2019 | 7,164 | | 2018 | 6,332 | | 2017 | 4,949 | | 2016 | 4,580 | | 2015 | 4,259 | | 2014 | 4,010 | | 2013 | 3,815 | | 2012 | 3,650 | | 2011 | 3,558 | | 2010 | 3,557 | | 2009 | 3,577 | | 2008 | 3,557 | | 2007 | 3,474 | | 2006 | 3,338 | | 2005 | 3,160 | | 2004 | 3,000 | | 2003 | 2,919 | | 2002 | 2,880 | | 2001 | 2,949 | | 2000 | 3,212 | | 1999 | 3,585 | | 1998 | 4,007 | | 1997 | 4,391 | | 1996 | 4,699 | | 1995 | 4,979 | | 1994 | 5,242 | | 1993 | 5,470 | | 1992 | 5,697 | | 1991 | 5,963 | | 1990 | 6,210 | | 1989 | 6,438 | | 1988 | 6,650 | | 1987 | 6,797 | | 1986 | 6,832 | | 1985 | 6,759 | | 1984 | 6,610 | | 1983 | 6,438 | | 1982 | 6,257 | | 1981 | 6,040 | | 1980 | 5,838 | | 1979 | 5,666 | | 1978 | 5,540 | | 1977 | 5,461 | | 1976 | 5,357 | | 1975 | 5,265 | | 1974 | 5,167 | | 1973 | 5,040 | | 1972 | 4,969 | | 1971 | 4,867 | | 1970 | 4,707 | | 1969 | 4,573 | | 1968 | 4,456 | | 1967 | 4,374 | | 1966 | 4,341 | | 1965 | 4,323 | | 1964 | 4,287 | | 1963 | 4,246 | | 1962 | 4,195 | | 1961 | 4,151 | | 1960 | 4,161 |
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