| Year | Value | | 2022 | 3,615 | | 2021 | 3,682 | | 2020 | 3,722 | | 2019 | 3,735 | | 2018 | 3,740 | | 2017 | 3,750 | | 2016 | 3,776 | | 2015 | 3,817 | | 2014 | 3,858 | | 2013 | 3,887 | | 2012 | 3,896 | | 2011 | 3,886 | | 2010 | 3,868 | | 2009 | 3,856 | | 2008 | 3,859 | | 2007 | 3,880 | | 2006 | 3,930 | | 2005 | 4,007 | | 2004 | 4,097 | | 2003 | 4,185 | | 2002 | 4,254 | | 2001 | 4,280 | | 2000 | 4,261 | | 1999 | 4,212 | | 1998 | 4,136 | | 1997 | 4,038 | | 1996 | 3,919 | | 1995 | 3,775 | | 1994 | 3,604 | | 1993 | 3,410 | | 1992 | 3,205 | | 1991 | 2,999 | | 1990 | 2,843 | | 1989 | 2,758 | | 1988 | 2,695 | | 1987 | 2,637 | | 1986 | 2,563 | | 1985 | 2,453 | | 1984 | 2,297 | | 1983 | 2,135 | | 1982 | 1,987 | | 1981 | 1,855 | | 1980 | 1,770 | | 1979 | 1,732 | | 1978 | 1,716 | | 1977 | 1,708 | | 1976 | 1,699 | | 1975 | 1,690 | | 1974 | 1,680 | | 1973 | 1,672 | | 1972 | 1,668 | | 1971 | 1,664 | | 1970 | 1,659 | | 1969 | 1,653 | | 1968 | 1,646 | | 1967 | 1,640 | | 1966 | 1,633 | | 1965 | 1,625 | | 1964 | 1,619 | | 1963 | 1,614 | | 1962 | 1,608 | | 1961 | 1,601 | | 1960 | 1,593 |
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