| Year | Value | | 2022 | 15,982 | | 2021 | 15,730 | | 2020 | 15,533 | | 2019 | 15,318 | | 2018 | 14,994 | | 2017 | 14,577 | | 2016 | 14,070 | | 2015 | 13,472 | | 2014 | 12,862 | | 2013 | 12,300 | | 2012 | 11,764 | | 2011 | 11,234 | | 2010 | 10,710 | | 2009 | 10,194 | | 2008 | 9,709 | | 2007 | 9,249 | | 2006 | 8,774 | | 2005 | 8,304 | | 2004 | 7,882 | | 2003 | 7,505 | | 2002 | 7,186 | | 2001 | 6,961 | | 2000 | 6,804 | | 1999 | 6,676 | | 1998 | 6,558 | | 1997 | 6,449 | | 1996 | 6,347 | | 1995 | 6,251 | | 1994 | 6,134 | | 1993 | 5,986 | | 1992 | 5,823 | | 1991 | 5,647 | | 1990 | 5,465 | | 1989 | 5,293 | | 1988 | 5,139 | | 1987 | 5,000 | | 1986 | 4,864 | | 1985 | 4,722 | | 1984 | 4,569 | | 1983 | 4,413 | | 1982 | 4,261 | | 1981 | 4,116 | | 1980 | 3,981 | | 1979 | 3,856 | | 1978 | 3,748 | | 1977 | 3,652 | | 1976 | 3,569 | | 1975 | 3,507 | | 1974 | 3,460 | | 1973 | 3,418 | | 1972 | 3,379 | | 1971 | 3,342 | | 1970 | 3,284 | | 1969 | 3,204 | | 1968 | 3,125 | | 1967 | 3,046 | | 1966 | 2,972 | | 1965 | 2,900 | | 1964 | 2,831 | | 1963 | 2,765 | | 1962 | 2,700 | | 1961 | 2,636 | | 1960 | 2,577 |
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