| Year | Value | | 2022 | 5,669 | | 2021 | 5,529 | | 2020 | 5,491 | | 2019 | 5,556 | | 2018 | 5,703 | | 2017 | 5,873 | | 2016 | 6,014 | | 2015 | 6,101 | | 2014 | 6,127 | | 2013 | 6,113 | | 2012 | 6,078 | | 2011 | 6,039 | | 2010 | 5,988 | | 2009 | 5,933 | | 2008 | 5,885 | | 2007 | 5,829 | | 2006 | 5,750 | | 2005 | 5,644 | | 2004 | 5,506 | | 2003 | 5,336 | | 2002 | 5,139 | | 2001 | 4,920 | | 2000 | 4,718 | | 1999 | 4,566 | | 1998 | 4,415 | | 1997 | 4,244 | | 1996 | 4,081 | | 1995 | 3,926 | | 1994 | 3,765 | | 1993 | 3,633 | | 1992 | 3,551 | | 1991 | 3,504 | | 1990 | 3,491 | | 1989 | 3,517 | | 1988 | 3,590 | | 1987 | 3,697 | | 1986 | 3,810 | | 1985 | 3,915 | | 1984 | 3,993 | | 1983 | 4,017 | | 1982 | 3,974 | | 1981 | 3,878 | | 1980 | 3,745 | | 1979 | 3,592 | | 1978 | 3,475 | | 1977 | 3,406 | | 1976 | 3,324 | | 1975 | 3,212 | | 1974 | 3,084 | | 1973 | 2,974 | | 1972 | 2,902 | | 1971 | 2,857 | | 1970 | 2,815 | | 1969 | 2,759 | | 1968 | 2,744 | | 1967 | 2,779 | | 1966 | 2,803 | | 1965 | 2,725 | | 1964 | 2,554 | | 1963 | 2,390 | | 1962 | 2,256 | | 1961 | 2,143 | | 1960 | 2,044 |
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