| Year | Value | | 2022 | 4,490 | | 2021 | 4,071 | | 2020 | 3,793 | | 2019 | 3,634 | | 2018 | 3,578 | | 2017 | 3,609 | | 2016 | 3,699 | | 2015 | 3,838 | | 2014 | 4,031 | | 2013 | 4,281 | | 2012 | 4,571 | | 2011 | 4,865 | | 2010 | 5,134 | | 2009 | 5,280 | | 2008 | 5,268 | | 2007 | 5,183 | | 2006 | 5,059 | | 2005 | 4,907 | | 2004 | 4,730 | | 2003 | 4,529 | | 2002 | 4,303 | | 2001 | 4,052 | | 2000 | 3,793 | | 1999 | 3,588 | | 1998 | 3,438 | | 1997 | 3,292 | | 1996 | 3,162 | | 1995 | 3,051 | | 1994 | 2,961 | | 1993 | 2,891 | | 1992 | 2,844 | | 1991 | 2,815 | | 1990 | 2,799 | | 1989 | 2,792 | | 1988 | 2,790 | | 1987 | 2,798 | | 1986 | 2,813 | | 1985 | 2,832 | | 1984 | 2,850 | | 1983 | 2,864 | | 1982 | 2,874 | | 1981 | 2,876 | | 1980 | 2,873 | | 1979 | 2,861 | | 1978 | 2,841 | | 1977 | 2,813 | | 1976 | 2,774 | | 1975 | 2,728 | | 1974 | 2,679 | | 1973 | 2,625 | | 1972 | 2,568 | | 1971 | 2,508 | | 1970 | 2,452 | | 1969 | 2,395 | | 1968 | 2,341 | | 1967 | 2,292 | | 1966 | 2,244 | | 1965 | 2,192 | | 1964 | 2,136 | | 1963 | 2,075 | | 1962 | 2,011 | | 1961 | 1,946 | | 1960 | 1,878 |
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