| Year | Value | | 2022 | 14,992 | | 2021 | 14,915 | | 2020 | 15,030 | | 2019 | 14,884 | | 2018 | 14,340 | | 2017 | 13,787 | | 2016 | 13,107 | | 2015 | 12,390 | | 2014 | 11,842 | | 2013 | 11,638 | | 2012 | 11,559 | | 2011 | 11,538 | | 2010 | 11,484 | | 2009 | 11,296 | | 2008 | 10,869 | | 2007 | 10,249 | | 2006 | 9,591 | | 2005 | 9,027 | | 2004 | 8,675 | | 2003 | 8,585 | | 2002 | 8,652 | | 2001 | 8,804 | | 2000 | 8,978 | | 1999 | 9,064 | | 1998 | 9,094 | | 1997 | 9,104 | | 1996 | 9,040 | | 1995 | 8,955 | | 1994 | 8,978 | | 1993 | 9,160 | | 1992 | 9,445 | | 1991 | 9,733 | | 1990 | 9,959 | | 1989 | 10,088 | | 1988 | 10,079 | | 1987 | 9,954 | | 1986 | 9,746 | | 1985 | 9,487 | | 1984 | 9,223 | | 1983 | 8,999 | | 1982 | 8,854 | | 1981 | 8,785 | | 1980 | 8,757 | | 1979 | 8,720 | | 1978 | 8,639 | | 1977 | 8,468 | | 1976 | 8,158 | | 1975 | 7,745 | | 1974 | 7,327 | | 1973 | 7,018 | | 1972 | 6,892 | | 1971 | 6,941 | | 1970 | 7,075 | | 1969 | 7,186 | | 1968 | 7,171 | | 1967 | 7,033 | | 1966 | 6,873 | | 1965 | 6,746 | | 1964 | 6,677 | | 1963 | 6,621 | | 1962 | 6,173 | | 1961 | 5,416 | | 1960 | 4,779 |
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