| Year | Value | | 2022 | 4,765 | | 2021 | 4,036 | | 2020 | 4,069 | | 2019 | 4,068 | | 2018 | 4,046 | | 2017 | 4,034 | | 2016 | 4,024 | | 2015 | 3,992 | | 2014 | 3,949 | | 2013 | 3,963 | | 2012 | 3,921 | | 2011 | 3,867 | | 2010 | 3,982 | | 2009 | 3,871 | | 2008 | 3,807 | | 2007 | 3,691 | | 2006 | 3,657 | | 2005 | 3,573 | | 2004 | 3,567 | | 2003 | 3,606 | | 2002 | 3,681 | | 2001 | 3,686 | | 2000 | 3,847 | | 1999 | 3,978 | | 1998 | 4,077 | | 1997 | 4,037 | | 1996 | 4,003 | | 1995 | 4,027 | | 1994 | 3,995 | | 1993 | 3,911 | | 1992 | 3,886 | | 1991 | 3,928 | | 1990 | 3,940 | | 1989 | 4,003 | | 1988 | 4,053 | | 1987 | 4,058 | | 1986 | 3,916 | | 1985 | 3,985 | | 1984 | 4,038 | | 1983 | 4,101 | | 1982 | 4,196 | | 1981 | 4,198 | | 1980 | 4,174 | | 1979 | 4,206 | | 1978 | 4,229 | | 1977 | 4,292 | | 1976 | 4,324 | | 1975 | 4,304 | | 1974 | 4,242 | | 1973 | 4,227 | | 1972 | 4,257 | | 1971 | 4,275 | | 1970 | 4,306 | | 1969 | 4,300 | | 1968 | 4,260 | | 1967 | 4,196 | | 1966 | 4,111 | | 1965 | 4,020 | | 1964 | 3,940 | | 1963 | 3,858 | | 1962 | 3,765 | | 1961 | 3,666 | | 1960 | 3,534 |
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