| Year | Value | | 2022 | 9,329 | | 2021 | 8,974 | | 2020 | 8,856 | | 2019 | 8,907 | | 2018 | 8,955 | | 2017 | 8,924 | | 2016 | 8,825 | | 2015 | 8,748 | | 2014 | 8,555 | | 2013 | 8,326 | | 2012 | 8,233 | | 2011 | 8,293 | | 2010 | 8,429 | | 2009 | 8,567 | | 2008 | 8,647 | | 2007 | 8,701 | | 2006 | 8,671 | | 2005 | 8,489 | | 2004 | 8,254 | | 2003 | 8,124 | | 2002 | 7,998 | | 2001 | 7,794 | | 2000 | 7,820 | | 1999 | 7,749 | | 1998 | 7,281 | | 1997 | 6,792 | | 1996 | 6,348 | | 1995 | 5,934 | | 1994 | 5,826 | | 1993 | 6,130 | | 1992 | 6,592 | | 1991 | 6,989 | | 1990 | 7,178 | | 1989 | 7,174 | | 1988 | 7,199 | | 1987 | 7,178 | | 1986 | 7,098 | | 1985 | 7,056 | | 1984 | 6,969 | | 1983 | 6,790 | | 1982 | 6,608 | | 1981 | 6,483 | | 1980 | 6,333 | | 1979 | 6,138 | | 1978 | 5,998 | | 1977 | 5,846 | | 1976 | 5,663 | | 1975 | 5,503 | | 1974 | 5,298 | | 1973 | 5,076 | | 1972 | 4,866 | | 1971 | 4,679 | | 1970 | 4,485 | | 1969 | 4,327 | | 1968 | 4,201 | | 1967 | 4,091 | | 1966 | 4,026 | | 1965 | 3,953 | | 1964 | 3,862 | | 1963 | 3,801 | | 1962 | 3,783 | | 1961 | 3,719 | | 1960 | 3,637 |
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