| Year | Value | | 2022 | 9,673 | | 2021 | 9,837 | | 2020 | 9,846 | | 2019 | 9,821 | | 2018 | 9,747 | | 2017 | 9,630 | | 2016 | 9,586 | | 2015 | 9,675 | | 2014 | 9,842 | | 2013 | 10,029 | | 2012 | 10,263 | | 2011 | 10,516 | | 2010 | 10,670 | | 2009 | 10,687 | | 2008 | 10,624 | | 2007 | 10,524 | | 2006 | 10,490 | | 2005 | 10,612 | | 2004 | 10,872 | | 2003 | 11,195 | | 2002 | 11,462 | | 2001 | 11,648 | | 2000 | 11,784 | | 1999 | 11,843 | | 1998 | 11,817 | | 1997 | 11,783 | | 1996 | 11,720 | | 1995 | 11,575 | | 1994 | 11,378 | | 1993 | 11,130 | | 1992 | 10,816 | | 1991 | 10,441 | | 1990 | 10,041 | | 1989 | 9,654 | | 1988 | 9,281 | | 1987 | 8,888 | | 1986 | 8,456 | | 1985 | 7,985 | | 1984 | 7,515 | | 1983 | 7,031 | | 1982 | 6,514 | | 1981 | 6,015 | | 1980 | 5,558 | | 1979 | 5,209 | | 1978 | 4,996 | | 1977 | 4,913 | | 1976 | 4,957 | | 1975 | 5,086 | | 1974 | 5,282 | | 1973 | 5,516 | | 1972 | 5,728 | | 1971 | 5,911 | | 1970 | 6,104 | | 1969 | 6,296 | | 1968 | 6,468 | | 1967 | 6,617 | | 1966 | 6,724 | | 1965 | 6,786 | | 1964 | 6,814 | | 1963 | 6,816 | | 1962 | 6,809 | | 1961 | 6,831 | | 1960 | 6,867 |
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