| Year | Value | | 2022 | 5,893 | | 2021 | 5,905 | | 2020 | 5,962 | | 2019 | 6,054 | | 2018 | 6,159 | | 2017 | 6,260 | | 2016 | 6,345 | | 2015 | 6,390 | | 2014 | 6,404 | | 2013 | 6,414 | | 2012 | 6,433 | | 2011 | 6,459 | | 2010 | 6,460 | | 2009 | 6,423 | | 2008 | 6,341 | | 2007 | 6,276 | | 2006 | 6,305 | | 2005 | 6,412 | | 2004 | 6,568 | | 2003 | 6,768 | | 2002 | 6,935 | | 2001 | 7,009 | | 2000 | 7,004 | | 1999 | 6,898 | | 1998 | 6,763 | | 1997 | 6,700 | | 1996 | 6,696 | | 1995 | 6,696 | | 1994 | 6,552 | | 1993 | 6,270 | | 1992 | 6,064 | | 1991 | 5,935 | | 1990 | 5,810 | | 1989 | 5,691 | | 1988 | 5,569 | | 1987 | 5,420 | | 1986 | 5,241 | | 1985 | 5,058 | | 1984 | 4,887 | | 1983 | 4,732 | | 1982 | 4,585 | | 1981 | 4,443 | | 1980 | 4,310 | | 1979 | 4,186 | | 1978 | 4,065 | | 1977 | 3,959 | | 1976 | 3,865 | | 1975 | 3,766 | | 1974 | 3,659 | | 1973 | 3,547 | | 1972 | 3,445 | | 1971 | 3,350 | | 1970 | 3,253 | | 1969 | 3,116 | | 1968 | 2,946 | | 1967 | 2,781 | | 1966 | 2,623 | | 1965 | 2,474 | | 1964 | 2,374 | | 1963 | 2,319 | | 1962 | 2,259 | | 1961 | 2,190 | | 1960 | 2,119 |
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