| Year | Value | | 2022 | 16,963 | | 2021 | 16,359 | | 2020 | 15,779 | | 2019 | 15,259 | | 2018 | 14,829 | | 2017 | 14,495 | | 2016 | 14,231 | | 2015 | 14,007 | | 2014 | 13,800 | | 2013 | 13,577 | | 2012 | 13,311 | | 2011 | 12,986 | | 2010 | 12,601 | | 2009 | 12,153 | | 2008 | 11,631 | | 2007 | 11,054 | | 2006 | 10,470 | | 2005 | 9,934 | | 2004 | 9,506 | | 2003 | 9,254 | | 2002 | 9,271 | | 2001 | 9,353 | | 2000 | 9,221 | | 1999 | 8,788 | | 1998 | 8,215 | | 1997 | 7,739 | | 1996 | 7,381 | | 1995 | 7,112 | | 1994 | 6,986 | | 1993 | 6,998 | | 1992 | 7,000 | | 1991 | 6,951 | | 1990 | 6,860 | | 1989 | 6,726 | | 1988 | 6,573 | | 1987 | 6,410 | | 1986 | 6,240 | | 1985 | 6,065 | | 1984 | 5,887 | | 1983 | 5,713 | | 1982 | 5,549 | | 1981 | 5,382 | | 1980 | 5,219 | | 1979 | 5,086 | | 1978 | 4,983 | | 1977 | 4,893 | | 1976 | 4,812 | | 1975 | 4,747 | | 1974 | 4,693 | | 1973 | 4,644 | | 1972 | 4,605 | | 1971 | 4,572 | | 1970 | 4,547 | | 1969 | 4,526 | | 1968 | 4,510 | | 1967 | 4,494 | | 1966 | 4,490 | | 1965 | 4,494 | | 1964 | 4,492 | | 1963 | 4,482 | | 1962 | 4,462 | | 1961 | 4,432 | | 1960 | 4,394 |
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