| Year | Value | | 2022 | 3,059 | | 2021 | 3,138 | | 2020 | 3,215 | | 2019 | 3,290 | | 2018 | 3,365 | | 2017 | 3,435 | | 2016 | 3,513 | | 2015 | 3,622 | | 2014 | 3,738 | | 2013 | 3,820 | | 2012 | 3,869 | | 2011 | 3,883 | | 2010 | 3,846 | | 2009 | 3,781 | | 2008 | 3,729 | | 2007 | 3,712 | | 2006 | 3,751 | | 2005 | 3,826 | | 2004 | 3,857 | | 2003 | 3,891 | | 2002 | 3,985 | | 2001 | 4,103 | | 2000 | 4,244 | | 1999 | 4,450 | | 1998 | 4,698 | | 1997 | 4,939 | | 1996 | 5,205 | | 1995 | 5,501 | | 1994 | 5,710 | | 1993 | 5,761 | | 1992 | 5,729 | | 1991 | 5,636 | | 1990 | 5,564 | | 1989 | 5,429 | | 1988 | 5,487 | | 1987 | 5,558 | | 1986 | 5,597 | | 1985 | 5,647 | | 1984 | 5,673 | | 1983 | 5,618 | | 1982 | 5,559 | | 1981 | 5,555 | | 1980 | 5,543 | | 1979 | 5,477 | | 1978 | 5,773 | | 1977 | 6,010 | | 1976 | 6,716 | | 1975 | 7,171 | | 1974 | 7,134 | | 1973 | 6,658 | | 1972 | 5,924 | | 1971 | 5,300 | | 1970 | 4,460 | | 1969 | 4,155 | | 1968 | 3,977 | | 1967 | 3,575 | | 1966 | 3,376 | | 1965 | 3,152 | | 1964 | 2,940 | | 1963 | 2,908 | | 1962 | 2,627 | | 1961 | 2,650 | | 1960 | 2,531 |
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