| Year | Value | | 2022 | 11,556 | | 2021 | 11,560 | | 2020 | 11,643 | | 2019 | 11,787 | | 2018 | 11,849 | | 2017 | 11,771 | | 2016 | 11,706 | | 2015 | 11,697 | | 2014 | 11,765 | | 2013 | 12,059 | | 2012 | 12,456 | | 2011 | 12,776 | | 2010 | 13,088 | | 2009 | 13,371 | | 2008 | 13,602 | | 2007 | 13,968 | | 2006 | 14,229 | | 2005 | 14,159 | | 2004 | 13,925 | | 2003 | 13,519 | | 2002 | 13,084 | | 2001 | 12,737 | | 2000 | 12,323 | | 1999 | 11,819 | | 1998 | 11,318 | | 1997 | 10,922 | | 1996 | 10,582 | | 1995 | 10,305 | | 1994 | 10,209 | | 1993 | 10,273 | | 1992 | 10,395 | | 1991 | 10,530 | | 1990 | 10,700 | | 1989 | 10,875 | | 1988 | 10,981 | | 1987 | 11,006 | | 1986 | 10,998 | | 1985 | 10,949 | | 1984 | 10,841 | | 1983 | 10,726 | | 1982 | 10,525 | | 1981 | 10,191 | | 1980 | 9,814 | | 1979 | 9,423 | | 1978 | 9,046 | | 1977 | 8,667 | | 1976 | 8,275 | | 1975 | 7,877 | | 1974 | 7,464 | | 1973 | 7,034 | | 1972 | 6,585 | | 1971 | 6,199 | | 1970 | 5,889 | | 1969 | 5,596 | | 1968 | 5,329 | | 1967 | 5,084 | | 1966 | 4,874 | | 1965 | 4,716 | | 1964 | 4,593 | | 1963 | 4,478 | | 1962 | 4,405 | | 1961 | 4,387 | | 1960 | 4,376 |
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