| Year | Value | | 2022 | 11,059 | | 2021 | 10,733 | | 2020 | 10,448 | | 2019 | 10,299 | | 2018 | 10,303 | | 2017 | 10,374 | | 2016 | 10,475 | | 2015 | 10,600 | | 2014 | 10,737 | | 2013 | 10,850 | | 2012 | 10,929 | | 2011 | 10,950 | | 2010 | 10,846 | | 2009 | 10,627 | | 2008 | 10,366 | | 2007 | 10,096 | | 2006 | 9,815 | | 2005 | 9,623 | | 2004 | 9,561 | | 2003 | 9,553 | | 2002 | 9,575 | | 2001 | 9,624 | | 2000 | 9,688 | | 1999 | 9,777 | | 1998 | 9,914 | | 1997 | 10,098 | | 1996 | 10,331 | | 1995 | 10,596 | | 1994 | 10,861 | | 1993 | 11,098 | | 1992 | 11,292 | | 1991 | 11,429 | | 1990 | 11,475 | | 1989 | 11,530 | | 1988 | 11,694 | | 1987 | 11,919 | | 1986 | 11,989 | | 1985 | 11,854 | | 1984 | 11,700 | | 1983 | 11,603 | | 1982 | 11,561 | | 1981 | 11,449 | | 1980 | 11,255 | | 1979 | 11,113 | | 1978 | 11,036 | | 1977 | 10,979 | | 1976 | 10,748 | | 1975 | 10,356 | | 1974 | 10,032 | | 1973 | 9,749 | | 1972 | 9,430 | | 1971 | 9,083 | | 1970 | 8,731 | | 1969 | 8,390 | | 1968 | 8,096 | | 1967 | 7,811 | | 1966 | 7,472 | | 1965 | 7,098 | | 1964 | 6,726 | | 1963 | 6,362 | | 1962 | 6,038 | | 1961 | 5,840 | | 1960 | 5,717 |
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