| Year | Value | | 2022 | 3,176 | | 2021 | 3,257 | | 2020 | 3,337 | | 2019 | 3,415 | | 2018 | 3,492 | | 2017 | 3,567 | | 2016 | 3,650 | | 2015 | 3,766 | | 2014 | 3,854 | | 2013 | 3,884 | | 2012 | 3,901 | | 2011 | 3,895 | | 2010 | 3,848 | | 2009 | 3,825 | | 2008 | 3,841 | | 2007 | 3,858 | | 2006 | 3,909 | | 2005 | 3,980 | | 2004 | 4,016 | | 2003 | 4,069 | | 2002 | 4,172 | | 2001 | 4,292 | | 2000 | 4,443 | | 1999 | 4,645 | | 1998 | 4,871 | | 1997 | 5,101 | | 1996 | 5,363 | | 1995 | 5,665 | | 1994 | 5,878 | | 1993 | 5,926 | | 1992 | 5,885 | | 1991 | 5,780 | | 1990 | 5,698 | | 1989 | 5,553 | | 1988 | 5,609 | | 1987 | 5,685 | | 1986 | 5,731 | | 1985 | 5,790 | | 1984 | 5,825 | | 1983 | 5,756 | | 1982 | 5,670 | | 1981 | 5,671 | | 1980 | 5,663 | | 1979 | 5,574 | | 1978 | 5,884 | | 1977 | 6,139 | | 1976 | 6,854 | | 1975 | 7,329 | | 1974 | 7,303 | | 1973 | 6,806 | | 1972 | 6,033 | | 1971 | 5,372 | | 1970 | 4,491 | | 1969 | 4,177 | | 1968 | 4,027 | | 1967 | 3,650 | | 1966 | 3,466 | | 1965 | 3,241 | | 1964 | 2,994 | | 1963 | 2,900 | | 1962 | 2,563 | | 1961 | 2,527 | | 1960 | 2,435 |
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