| Year | Value | | 2022 | 4,253 | | 2021 | 4,296 | | 2020 | 4,344 | | 2019 | 4,423 | | 2018 | 4,524 | | 2017 | 4,626 | | 2016 | 4,748 | | 2015 | 4,894 | | 2014 | 5,070 | | 2013 | 5,276 | | 2012 | 5,489 | | 2011 | 5,686 | | 2010 | 5,855 | | 2009 | 5,983 | | 2008 | 6,066 | | 2007 | 6,114 | | 2006 | 6,129 | | 2005 | 6,129 | | 2004 | 6,152 | | 2003 | 6,204 | | 2002 | 6,255 | | 2001 | 6,290 | | 2000 | 6,280 | | 1999 | 6,181 | | 1998 | 6,013 | | 1997 | 5,838 | | 1996 | 5,682 | | 1995 | 5,536 | | 1994 | 5,395 | | 1993 | 5,266 | | 1992 | 5,144 | | 1991 | 5,025 | | 1990 | 4,927 | | 1989 | 4,855 | | 1988 | 4,777 | | 1987 | 4,677 | | 1986 | 4,542 | | 1985 | 4,321 | | 1984 | 4,039 | | 1983 | 3,751 | | 1982 | 3,461 | | 1981 | 3,200 | | 1980 | 3,024 | | 1979 | 2,912 | | 1978 | 2,833 | | 1977 | 2,775 | | 1976 | 2,704 | | 1975 | 2,622 | | 1974 | 2,545 | | 1973 | 2,489 | | 1972 | 2,438 | | 1971 | 2,377 | | 1970 | 2,297 | | 1969 | 2,193 | | 1968 | 2,082 | | 1967 | 1,988 | | 1966 | 1,912 | | 1965 | 1,853 | | 1964 | 1,811 | | 1963 | 1,783 | | 1962 | 1,767 | | 1961 | 1,756 | | 1960 | 1,747 |
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