| Year | Value | | 2022 | 20,639 | | 2021 | 19,305 | | 2020 | 17,736 | | 2019 | 16,368 | | 2018 | 15,285 | | 2017 | 14,300 | | 2016 | 13,435 | | 2015 | 12,696 | | 2014 | 11,981 | | 2013 | 11,365 | | 2012 | 10,985 | | 2011 | 10,772 | | 2010 | 10,609 | | 2009 | 10,477 | | 2008 | 10,378 | | 2007 | 10,204 | | 2006 | 9,908 | | 2005 | 9,582 | | 2004 | 9,286 | | 2003 | 9,077 | | 2002 | 9,045 | | 2001 | 9,224 | | 2000 | 9,453 | | 1999 | 9,579 | | 1998 | 9,551 | | 1997 | 9,401 | | 1996 | 9,075 | | 1995 | 8,616 | | 1994 | 8,085 | | 1993 | 7,538 | | 1992 | 7,106 | | 1991 | 6,771 | | 1990 | 6,565 | | 1989 | 6,504 | | 1988 | 6,491 | | 1987 | 6,421 | | 1986 | 6,271 | | 1985 | 6,092 | | 1984 | 5,857 | | 1983 | 5,547 | | 1982 | 5,248 | | 1981 | 4,982 | | 1980 | 4,759 | | 1979 | 4,570 | | 1978 | 4,408 | | 1977 | 4,282 | | 1976 | 4,159 | | 1975 | 4,051 | | 1974 | 3,949 | | 1973 | 3,845 | | 1972 | 3,723 | | 1971 | 3,568 | | 1970 | 3,392 | | 1969 | 3,214 | | 1968 | 3,049 | | 1967 | 2,907 | | 1966 | 2,785 | | 1965 | 2,684 | | 1964 | 2,607 | | 1963 | 2,539 | | 1962 | 2,422 | | 1961 | 2,223 | | 1960 | 2,069 |
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