| Year | Value | | 2022 | 3,853 | | 2021 | 3,802 | | 2020 | 3,757 | | 2019 | 3,694 | | 2018 | 3,619 | | 2017 | 3,561 | | 2016 | 3,517 | | 2015 | 3,488 | | 2014 | 3,474 | | 2013 | 3,472 | | 2012 | 3,476 | | 2011 | 3,489 | | 2010 | 3,508 | | 2009 | 3,528 | | 2008 | 3,550 | | 2007 | 3,574 | | 2006 | 3,600 | | 2005 | 3,635 | | 2004 | 3,678 | | 2003 | 3,730 | | 2002 | 3,794 | | 2001 | 3,874 | | 2000 | 3,974 | | 1999 | 4,101 | | 1998 | 4,261 | | 1997 | 4,441 | | 1996 | 4,627 | | 1995 | 4,817 | | 1994 | 4,992 | | 1993 | 5,139 | | 1992 | 5,275 | | 1991 | 5,435 | | 1990 | 5,488 | | 1989 | 5,413 | | 1988 | 5,339 | | 1987 | 5,270 | | 1986 | 5,203 | | 1985 | 5,132 | | 1984 | 5,059 | | 1983 | 4,974 | | 1982 | 4,874 | | 1981 | 4,765 | | 1980 | 4,644 | | 1979 | 4,597 | | 1978 | 4,249 | | 1977 | 3,563 | | 1976 | 2,968 | | 1975 | 2,456 | | 1974 | 2,023 | | 1973 | 1,790 | | 1972 | 1,711 | | 1971 | 1,646 | | 1970 | 1,602 | | 1969 | 1,577 | | 1968 | 1,569 | | 1967 | 1,568 | | 1966 | 1,586 | | 1965 | 1,632 | | 1964 | 1,701 | | 1963 | 1,765 | | 1962 | 1,809 | | 1961 | 1,845 | | 1960 | 1,852 |
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