| Year | Value | | 2022 | 24,380 | | 2021 | 23,873 | | 2020 | 23,690 | | 2019 | 22,860 | | 2018 | 21,996 | | 2017 | 21,243 | | 2016 | 20,316 | | 2015 | 19,343 | | 2014 | 18,482 | | 2013 | 17,660 | | 2012 | 16,851 | | 2011 | 16,098 | | 2010 | 15,375 | | 2009 | 14,647 | | 2008 | 13,936 | | 2007 | 13,247 | | 2006 | 12,573 | | 2005 | 11,898 | | 2004 | 11,218 | | 2003 | 10,531 | | 2002 | 9,856 | | 2001 | 9,222 | | 2000 | 8,650 | | 1999 | 8,135 | | 1998 | 7,688 | | 1997 | 7,311 | | 1996 | 6,979 | | 1995 | 6,681 | | 1994 | 6,425 | | 1993 | 6,212 | | 1992 | 6,027 | | 1991 | 5,863 | | 1990 | 5,713 | | 1989 | 5,568 | | 1988 | 5,416 | | 1987 | 5,257 | | 1986 | 5,116 | | 1985 | 5,014 | | 1984 | 4,947 | | 1983 | 4,916 | | 1982 | 4,921 | | 1981 | 4,924 | | 1980 | 4,904 | | 1979 | 4,864 | | 1978 | 4,805 | | 1977 | 4,732 | | 1976 | 4,657 | | 1975 | 4,584 | | 1974 | 4,514 | | 1973 | 4,442 | | 1972 | 4,370 | | 1971 | 4,308 | | 1970 | 4,265 | | 1969 | 4,241 | | 1968 | 4,229 | | 1967 | 4,223 | | 1966 | 4,217 | | 1965 | 4,210 | | 1964 | 4,207 | | 1963 | 4,211 | | 1962 | 4,218 | | 1961 | 4,215 | | 1960 | 4,196 |
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