| Year | Value | | 2022 | 5,867 | | 2021 | 5,860 | | 2020 | 5,865 | | 2019 | 5,886 | | 2018 | 5,925 | | 2017 | 5,971 | | 2016 | 6,025 | | 2015 | 6,095 | | 2014 | 6,192 | | 2013 | 6,284 | | 2012 | 6,337 | | 2011 | 6,347 | | 2010 | 6,380 | | 2009 | 6,442 | | 2008 | 6,519 | | 2007 | 6,664 | | 2006 | 6,887 | | 2005 | 7,177 | | 2004 | 7,450 | | 2003 | 7,664 | | 2002 | 7,820 | | 2001 | 7,898 | | 2000 | 7,922 | | 1999 | 7,993 | | 1998 | 8,109 | | 1997 | 8,221 | | 1996 | 8,351 | | 1995 | 8,486 | | 1994 | 8,546 | | 1993 | 8,465 | | 1992 | 8,307 | | 1991 | 8,199 | | 1990 | 8,154 | | 1989 | 8,107 | | 1988 | 8,050 | | 1987 | 7,973 | | 1986 | 7,878 | | 1985 | 7,768 | | 1984 | 7,644 | | 1983 | 7,508 | | 1982 | 7,360 | | 1981 | 7,200 | | 1980 | 7,024 | | 1979 | 6,832 | | 1978 | 6,642 | | 1977 | 6,501 | | 1976 | 6,414 | | 1975 | 6,345 | | 1974 | 6,246 | | 1973 | 6,102 | | 1972 | 5,943 | | 1971 | 5,769 | | 1970 | 5,584 | | 1969 | 5,405 | | 1968 | 5,236 | | 1967 | 5,074 | | 1966 | 4,915 | | 1965 | 4,761 | | 1964 | 4,611 | | 1963 | 4,465 | | 1962 | 4,318 | | 1961 | 4,171 | | 1960 | 4,027 |
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