| Year | Value | | 2022 | 13,720 | | 2021 | 13,102 | | 2020 | 12,742 | | 2019 | 12,334 | | 2018 | 11,925 | | 2017 | 11,605 | | 2016 | 11,240 | | 2015 | 10,914 | | 2014 | 10,705 | | 2013 | 10,503 | | 2012 | 10,291 | | 2011 | 10,315 | | 2010 | 10,627 | | 2009 | 11,101 | | 2008 | 11,587 | | 2007 | 11,804 | | 2006 | 11,494 | | 2005 | 11,015 | | 2004 | 10,850 | | 2003 | 10,788 | | 2002 | 10,744 | | 2001 | 10,763 | | 2000 | 10,630 | | 1999 | 10,360 | | 1998 | 10,162 | | 1997 | 9,968 | | 1996 | 9,687 | | 1995 | 9,540 | | 1994 | 9,445 | | 1993 | 9,179 | | 1992 | 8,925 | | 1991 | 8,746 | | 1990 | 8,487 | | 1989 | 8,171 | | 1988 | 7,834 | | 1987 | 7,455 | | 1986 | 7,040 | | 1985 | 6,564 | | 1984 | 6,119 | | 1983 | 5,784 | | 1982 | 5,531 | | 1981 | 5,371 | | 1980 | 5,319 | | 1979 | 5,338 | | 1978 | 5,380 | | 1977 | 5,434 | | 1976 | 5,566 | | 1975 | 5,765 | | 1974 | 5,884 | | 1973 | 5,939 | | 1972 | 5,957 | | 1971 | 5,880 | | 1970 | 5,788 | | 1969 | 5,723 | | 1968 | 5,656 | | 1967 | 5,557 | | 1966 | 5,500 | | 1965 | 5,482 | | 1964 | 5,399 | | 1963 | 5,280 | | 1962 | 5,193 | | 1961 | 5,097 | | 1960 | 4,931 |
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