| Year | Value | | 2022 | 16,480 | | 2021 | 15,984 | | 2020 | 15,393 | | 2019 | 14,669 | | 2018 | 13,842 | | 2017 | 12,987 | | 2016 | 12,133 | | 2015 | 11,316 | | 2014 | 10,581 | | 2013 | 9,942 | | 2012 | 9,400 | | 2011 | 8,967 | | 2010 | 8,639 | | 2009 | 8,395 | | 2008 | 8,235 | | 2007 | 8,150 | | 2006 | 8,120 | | 2005 | 8,132 | | 2004 | 8,170 | | 2003 | 8,222 | | 2002 | 8,280 | | 2001 | 8,340 | | 2000 | 8,404 | | 1999 | 8,479 | | 1998 | 8,557 | | 1997 | 8,632 | | 1996 | 8,689 | | 1995 | 8,706 | | 1994 | 8,664 | | 1993 | 8,554 | | 1992 | 8,413 | | 1991 | 8,300 | | 1990 | 8,114 | | 1989 | 7,838 | | 1988 | 7,580 | | 1987 | 7,342 | | 1986 | 7,120 | | 1985 | 6,906 | | 1984 | 6,691 | | 1983 | 6,465 | | 1982 | 6,231 | | 1981 | 5,996 | | 1980 | 5,767 | | 1979 | 5,664 | | 1978 | 5,778 | | 1977 | 5,940 | | 1976 | 5,999 | | 1975 | 5,937 | | 1974 | 5,740 | | 1973 | 5,478 | | 1972 | 5,238 | | 1971 | 5,086 | | 1970 | 5,028 | | 1969 | 5,057 | | 1968 | 5,181 | | 1967 | 5,356 | | 1966 | 5,517 | | 1965 | 5,620 | | 1964 | 5,665 | | 1963 | 5,606 | | 1962 | 5,444 | | 1961 | 5,282 | | 1960 | 5,166 |
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