| Year | Value | | 2022 | 6,662 | | 2021 | 6,402 | | 2020 | 6,240 | | 2019 | 6,125 | | 2018 | 6,032 | | 2017 | 5,930 | | 2016 | 5,820 | | 2015 | 5,716 | | 2014 | 5,618 | | 2013 | 5,500 | | 2012 | 5,310 | | 2011 | 5,055 | | 2010 | 4,806 | | 2009 | 4,619 | | 2008 | 4,536 | | 2007 | 4,555 | | 2006 | 4,610 | | 2005 | 4,628 | | 2004 | 4,584 | | 2003 | 4,388 | | 2002 | 4,070 | | 2001 | 3,764 | | 2000 | 3,504 | | 1999 | 3,294 | | 1998 | 3,112 | | 1997 | 2,939 | | 1996 | 2,766 | | 1995 | 2,589 | | 1994 | 2,445 | | 1993 | 2,342 | | 1992 | 2,244 | | 1991 | 2,148 | | 1990 | 2,069 | | 1989 | 2,002 | | 1988 | 1,947 | | 1987 | 1,922 | | 1986 | 1,922 | | 1985 | 1,939 | | 1984 | 1,982 | | 1983 | 2,047 | | 1982 | 2,129 | | 1981 | 2,221 | | 1980 | 2,317 | | 1979 | 2,384 | | 1978 | 2,406 | | 1977 | 2,404 | | 1976 | 2,398 | | 1975 | 2,405 | | 1974 | 2,431 | | 1973 | 2,469 | | 1972 | 2,507 | | 1971 | 2,522 | | 1970 | 2,533 | | 1969 | 2,572 | | 1968 | 2,615 | | 1967 | 2,627 | | 1966 | 2,594 | | 1965 | 2,519 | | 1964 | 2,377 | | 1963 | 2,107 | | 1962 | 1,797 | | 1961 | 1,621 | | 1960 | 1,544 |
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