| Year | Value | | 2022 | 5,898 | | 2021 | 5,740 | | 2020 | 5,546 | | 2019 | 5,400 | | 2018 | 5,307 | | 2017 | 5,215 | | 2016 | 5,147 | | 2015 | 5,116 | | 2014 | 5,137 | | 2013 | 5,211 | | 2012 | 5,317 | | 2011 | 5,438 | | 2010 | 5,565 | | 2009 | 5,636 | | 2008 | 5,655 | | 2007 | 5,684 | | 2006 | 5,738 | | 2005 | 5,821 | | 2004 | 5,935 | | 2003 | 6,078 | | 2002 | 6,249 | | 2001 | 6,444 | | 2000 | 6,619 | | 1999 | 6,680 | | 1998 | 6,628 | | 1997 | 6,536 | | 1996 | 6,455 | | 1995 | 6,440 | | 1994 | 6,502 | | 1993 | 6,587 | | 1992 | 6,630 | | 1991 | 6,609 | | 1990 | 6,503 | | 1989 | 6,275 | | 1988 | 5,992 | | 1987 | 5,770 | | 1986 | 5,636 | | 1985 | 5,543 | | 1984 | 5,454 | | 1983 | 5,402 | | 1982 | 5,393 | | 1981 | 5,385 | | 1980 | 5,377 | | 1979 | 5,297 | | 1978 | 5,094 | | 1977 | 4,854 | | 1976 | 4,605 | | 1975 | 4,317 | | 1974 | 4,003 | | 1973 | 3,700 | | 1972 | 3,420 | | 1971 | 3,187 | | 1970 | 3,012 | | 1969 | 2,871 | | 1968 | 2,758 | | 1967 | 2,679 | | 1966 | 2,609 | | 1965 | 2,531 | | 1964 | 2,438 | | 1963 | 2,330 | | 1962 | 2,209 | | 1961 | 2,086 | | 1960 | 1,974 |
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