| Year | Value | | 2022 | 4,840 | | 2021 | 4,777 | | 2020 | 4,704 | | 2019 | 4,628 | | 2018 | 4,536 | | 2017 | 4,422 | | 2016 | 4,283 | | 2015 | 4,120 | | 2014 | 3,967 | | 2013 | 3,810 | | 2012 | 3,635 | | 2011 | 3,476 | | 2010 | 3,316 | | 2009 | 3,136 | | 2008 | 2,990 | | 2007 | 2,892 | | 2006 | 2,823 | | 2005 | 2,795 | | 2004 | 2,818 | | 2003 | 2,888 | | 2002 | 2,988 | | 2001 | 3,092 | | 2000 | 3,181 | | 1999 | 3,239 | | 1998 | 3,242 | | 1997 | 3,191 | | 1996 | 3,104 | | 1995 | 2,998 | | 1994 | 2,888 | | 1993 | 2,783 | | 1992 | 2,685 | | 1991 | 2,583 | | 1990 | 2,481 | | 1989 | 2,386 | | 1988 | 2,299 | | 1987 | 2,226 | | 1986 | 2,172 | | 1985 | 2,127 | | 1984 | 2,077 | | 1983 | 2,022 | | 1982 | 1,959 | | 1981 | 1,889 | | 1980 | 1,817 | | 1979 | 1,747 | | 1978 | 1,705 | | 1977 | 1,682 | | 1976 | 1,655 | | 1975 | 1,639 | | 1974 | 1,639 | | 1973 | 1,638 | | 1972 | 1,609 | | 1971 | 1,565 | | 1970 | 1,526 | | 1969 | 1,504 | | 1968 | 1,502 | | 1967 | 1,506 | | 1966 | 1,507 | | 1965 | 1,508 | | 1964 | 1,509 | | 1963 | 1,507 | | 1962 | 1,504 | | 1961 | 1,495 | | 1960 | 1,481 |
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