| Year | Value | | 2022 | 3,594 | | 2021 | 3,605 | | 2020 | 3,622 | | 2019 | 3,644 | | 2018 | 3,656 | | 2017 | 3,647 | | 2016 | 3,626 | | 2015 | 3,601 | | 2014 | 3,582 | | 2013 | 3,582 | | 2012 | 3,601 | | 2011 | 3,645 | | 2010 | 3,716 | | 2009 | 3,797 | | 2008 | 3,878 | | 2007 | 3,943 | | 2006 | 3,973 | | 2005 | 3,966 | | 2004 | 3,927 | | 2003 | 3,862 | | 2002 | 3,777 | | 2001 | 3,664 | | 2000 | 3,523 | | 1999 | 3,360 | | 1998 | 3,177 | | 1997 | 2,982 | | 1996 | 2,796 | | 1995 | 2,632 | | 1994 | 2,495 | | 1993 | 2,389 | | 1992 | 2,305 | | 1991 | 2,223 | | 1990 | 2,154 | | 1989 | 2,087 | | 1988 | 1,995 | | 1987 | 1,891 | | 1986 | 1,793 | | 1985 | 1,717 | | 1984 | 1,668 | | 1983 | 1,643 | | 1982 | 1,632 | | 1981 | 1,626 | | 1980 | 1,618 | | 1979 | 1,608 | | 1978 | 1,599 | | 1977 | 1,593 | | 1976 | 1,589 | | 1975 | 1,584 | | 1974 | 1,578 | | 1973 | 1,572 | | 1972 | 1,566 | | 1971 | 1,558 | | 1970 | 1,549 | | 1969 | 1,541 | | 1968 | 1,534 | | 1967 | 1,528 | | 1966 | 1,519 | | 1965 | 1,508 | | 1964 | 1,493 | | 1963 | 1,476 | | 1962 | 1,457 | | 1961 | 1,440 | | 1960 | 1,424 |
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