| Year | Value | | 2022 | 25,242 | | 2021 | 24,407 | | 2020 | 23,390 | | 2019 | 22,523 | | 2018 | 21,864 | | 2017 | 21,289 | | 2016 | 20,725 | | 2015 | 20,110 | | 2014 | 18,617 | | 2013 | 16,197 | | 2012 | 14,383 | | 2011 | 13,351 | | 2010 | 12,407 | | 2009 | 11,126 | | 2008 | 9,632 | | 2007 | 8,373 | | 2006 | 7,370 | | 2005 | 6,628 | | 2004 | 6,120 | | 2003 | 5,827 | | 2002 | 5,701 | | 2001 | 5,651 | | 2000 | 5,612 | | 1999 | 5,554 | | 1998 | 5,465 | | 1997 | 5,347 | | 1996 | 5,199 | | 1995 | 5,025 | | 1994 | 4,839 | | 1993 | 4,666 | | 1992 | 4,522 | | 1991 | 4,403 | | 1990 | 4,305 | | 1989 | 4,226 | | 1988 | 4,125 | | 1987 | 3,976 | | 1986 | 3,807 | | 1985 | 3,631 | | 1984 | 3,453 | | 1983 | 3,284 | | 1982 | 3,126 | | 1981 | 2,981 | | 1980 | 2,853 | | 1979 | 2,739 | | 1978 | 2,639 | | 1977 | 2,548 | | 1976 | 2,458 | | 1975 | 2,370 | | 1974 | 2,276 | | 1973 | 2,173 | | 1972 | 2,072 | | 1971 | 1,976 | | 1970 | 1,879 | | 1969 | 1,785 | | 1968 | 1,702 | | 1967 | 1,615 | | 1966 | 1,523 | | 1965 | 1,427 | | 1964 | 1,365 | | 1963 | 1,336 | | 1962 | 1,315 | | 1961 | 1,302 | | 1960 | 1,300 |
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