| Year | Value | | 2022 | 20,764 | | 2021 | 19,814 | | 2020 | 18,937 | | 2019 | 18,151 | | 2018 | 17,431 | | 2017 | 16,775 | | 2016 | 16,175 | | 2015 | 15,625 | | 2014 | 15,108 | | 2013 | 14,620 | | 2012 | 14,160 | | 2011 | 13,727 | | 2010 | 13,326 | | 2009 | 12,958 | | 2008 | 12,583 | | 2007 | 12,208 | | 2006 | 11,843 | | 2005 | 11,509 | | 2004 | 11,219 | | 2003 | 10,935 | | 2002 | 10,662 | | 2001 | 10,406 | | 2000 | 10,159 | | 1999 | 9,912 | | 1998 | 9,675 | | 1997 | 9,454 | | 1996 | 9,204 | | 1995 | 8,902 | | 1994 | 8,548 | | 1993 | 8,539 | | 1992 | 8,597 | | 1991 | 8,343 | | 1990 | 8,083 | | 1989 | 7,817 | | 1988 | 7,546 | | 1987 | 7,274 | | 1986 | 7,010 | | 1985 | 6,753 | | 1984 | 6,500 | | 1983 | 6,247 | | 1982 | 6,003 | | 1981 | 5,779 | | 1980 | 5,583 | | 1979 | 5,415 | | 1978 | 5,278 | | 1977 | 5,167 | | 1976 | 5,069 | | 1975 | 4,981 | | 1974 | 4,907 | | 1973 | 4,840 | | 1972 | 4,780 | | 1971 | 4,731 | | 1970 | 4,692 | | 1969 | 4,660 | | 1968 | 4,641 | | 1967 | 4,645 | | 1966 | 4,661 | | 1965 | 4,685 | | 1964 | 4,725 | | 1963 | 4,769 | | 1962 | 4,800 | | 1961 | 4,825 | | 1960 | 4,852 |
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