| Year | Value | | 2022 | 3,731 | | 2021 | 3,773 | | 2020 | 3,808 | | 2019 | 3,802 | | 2018 | 3,769 | | 2017 | 3,737 | | 2016 | 3,706 | | 2015 | 3,672 | | 2014 | 3,642 | | 2013 | 3,611 | | 2012 | 3,577 | | 2011 | 3,544 | | 2010 | 3,514 | | 2009 | 3,494 | | 2008 | 3,482 | | 2007 | 3,477 | | 2006 | 3,484 | | 2005 | 3,506 | | 2004 | 3,543 | | 2003 | 3,600 | | 2002 | 3,675 | | 2001 | 3,768 | | 2000 | 3,882 | | 1999 | 4,016 | | 1998 | 4,168 | | 1997 | 4,335 | | 1996 | 4,505 | | 1995 | 4,667 | | 1994 | 4,817 | | 1993 | 4,954 | | 1992 | 5,087 | | 1991 | 5,253 | | 1990 | 5,288 | | 1989 | 5,157 | | 1988 | 5,008 | | 1987 | 4,840 | | 1986 | 4,649 | | 1985 | 4,436 | | 1984 | 4,201 | | 1983 | 3,941 | | 1982 | 3,658 | | 1981 | 3,357 | | 1980 | 3,041 | | 1979 | 2,826 | | 1978 | 2,627 | | 1977 | 2,354 | | 1976 | 2,119 | | 1975 | 1,922 | | 1974 | 1,759 | | 1973 | 1,664 | | 1972 | 1,631 | | 1971 | 1,622 | | 1970 | 1,607 | | 1969 | 1,588 | | 1968 | 1,565 | | 1967 | 1,520 | | 1966 | 1,496 | | 1965 | 1,509 | | 1964 | 1,553 | | 1963 | 1,588 | | 1962 | 1,599 | | 1961 | 1,615 | | 1960 | 1,597 |
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