| Year | Value | | 2022 | 3,617 | | 2021 | 3,647 | | 2020 | 3,714 | | 2019 | 3,806 | | 2018 | 3,915 | | 2017 | 4,021 | | 2016 | 4,149 | | 2015 | 4,309 | | 2014 | 4,479 | | 2013 | 4,666 | | 2012 | 4,851 | | 2011 | 4,998 | | 2010 | 5,072 | | 2009 | 5,081 | | 2008 | 5,062 | | 2007 | 5,042 | | 2006 | 5,055 | | 2005 | 5,137 | | 2004 | 5,292 | | 2003 | 5,476 | | 2002 | 5,659 | | 2001 | 5,837 | | 2000 | 5,988 | | 1999 | 6,076 | | 1998 | 6,126 | | 1997 | 6,162 | | 1996 | 6,196 | | 1995 | 6,241 | | 1994 | 6,298 | | 1993 | 6,337 | | 1992 | 6,338 | | 1991 | 6,307 | | 1990 | 6,239 | | 1989 | 6,174 | | 1988 | 6,171 | | 1987 | 6,230 | | 1986 | 6,330 | | 1985 | 6,447 | | 1984 | 6,564 | | 1983 | 6,657 | | 1982 | 6,722 | | 1981 | 6,771 | | 1980 | 6,822 | | 1979 | 6,854 | | 1978 | 6,826 | | 1977 | 6,729 | | 1976 | 6,571 | | 1975 | 6,369 | | 1974 | 6,156 | | 1973 | 5,964 | | 1972 | 5,796 | | 1971 | 5,654 | | 1970 | 5,533 | | 1969 | 5,433 | | 1968 | 5,294 | | 1967 | 5,109 | | 1966 | 4,908 | | 1965 | 4,671 | | 1964 | 4,412 | | 1963 | 4,205 | | 1962 | 4,068 | | 1961 | 3,972 | | 1960 | 3,941 |
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