| Year | Value | | 2022 | 9,437 | | 2021 | 9,263 | | 2020 | 9,101 | | 2019 | 9,036 | | 2018 | 9,219 | | 2017 | 9,523 | | 2016 | 9,721 | | 2015 | 9,760 | | 2014 | 9,776 | | 2013 | 9,811 | | 2012 | 9,849 | | 2011 | 9,775 | | 2010 | 9,559 | | 2009 | 9,324 | | 2008 | 9,175 | | 2007 | 9,029 | | 2006 | 8,864 | | 2005 | 8,841 | | 2004 | 8,847 | | 2003 | 8,779 | | 2002 | 8,770 | | 2001 | 8,820 | | 2000 | 8,922 | | 1999 | 9,052 | | 1998 | 9,177 | | 1997 | 9,265 | | 1996 | 9,262 | | 1995 | 9,171 | | 1994 | 8,984 | | 1993 | 8,713 | | 1992 | 8,452 | | 1991 | 8,224 | | 1990 | 8,004 | | 1989 | 7,798 | | 1988 | 7,597 | | 1987 | 7,352 | | 1986 | 7,088 | | 1985 | 6,829 | | 1984 | 6,583 | | 1983 | 6,353 | | 1982 | 6,134 | | 1981 | 5,916 | | 1980 | 5,719 | | 1979 | 5,570 | | 1978 | 5,453 | | 1977 | 5,332 | | 1976 | 5,215 | | 1975 | 5,134 | | 1974 | 5,068 | | 1973 | 4,981 | | 1972 | 4,891 | | 1971 | 4,704 | | 1970 | 4,406 | | 1969 | 4,058 | | 1968 | 3,824 | | 1967 | 3,676 | | 1966 | 3,553 | | 1965 | 3,453 | | 1964 | 3,383 | | 1963 | 3,322 | | 1962 | 3,267 | | 1961 | 3,199 | | 1960 | 3,112 |
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