| Year | Value | | 2022 | 5,077 | | 2021 | 5,132 | | 2020 | 5,175 | | 2019 | 5,209 | | 2018 | 5,229 | | 2017 | 5,235 | | 2016 | 5,229 | | 2015 | 5,209 | | 2014 | 5,177 | | 2013 | 5,129 | | 2012 | 5,065 | | 2011 | 4,984 | | 2010 | 4,907 | | 2009 | 4,839 | | 2008 | 4,773 | | 2007 | 4,721 | | 2006 | 4,687 | | 2005 | 4,729 | | 2004 | 4,849 | | 2003 | 4,977 | | 2002 | 5,142 | | 2001 | 5,324 | | 2000 | 5,423 | | 1999 | 5,487 | | 1998 | 5,610 | | 1997 | 5,788 | | 1996 | 6,015 | | 1995 | 6,262 | | 1994 | 6,508 | | 1993 | 6,706 | | 1992 | 6,884 | | 1991 | 7,048 | | 1990 | 7,151 | | 1989 | 7,161 | | 1988 | 7,135 | | 1987 | 7,027 | | 1986 | 6,761 | | 1985 | 6,541 | | 1984 | 6,387 | | 1983 | 6,210 | | 1982 | 6,085 | | 1981 | 6,086 | | 1980 | 6,138 | | 1979 | 6,208 | | 1978 | 6,305 | | 1977 | 6,388 | | 1976 | 6,449 | | 1975 | 6,487 | | 1974 | 6,496 | | 1973 | 6,502 | | 1972 | 6,583 | | 1971 | 6,795 | | 1970 | 7,133 | | 1969 | 7,550 | | 1968 | 7,977 | | 1967 | 8,349 | | 1966 | 8,654 | | 1965 | 8,923 | | 1964 | 9,149 | | 1963 | 9,321 | | 1962 | 9,435 | | 1961 | 9,462 | | 1960 | 9,354 |
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