| Year | Value | | 2022 | 4,758 | | 2021 | 4,576 | | 2020 | 4,434 | | 2019 | 4,400 | | 2018 | 4,472 | | 2017 | 4,578 | | 2016 | 4,699 | | 2015 | 4,824 | | 2014 | 4,941 | | 2013 | 5,044 | | 2012 | 5,146 | | 2011 | 5,270 | | 2010 | 5,419 | | 2009 | 5,572 | | 2008 | 5,730 | | 2007 | 5,905 | | 2006 | 6,084 | | 2005 | 6,255 | | 2004 | 6,393 | | 2003 | 6,480 | | 2002 | 6,515 | | 2001 | 6,509 | | 2000 | 6,488 | | 1999 | 6,478 | | 1998 | 6,493 | | 1997 | 6,508 | | 1996 | 6,489 | | 1995 | 6,413 | | 1994 | 6,277 | | 1993 | 6,107 | | 1992 | 5,952 | | 1991 | 5,830 | | 1990 | 5,697 | | 1989 | 5,532 | | 1988 | 5,386 | | 1987 | 5,284 | | 1986 | 5,204 | | 1985 | 5,163 | | 1984 | 5,154 | | 1983 | 5,116 | | 1982 | 5,038 | | 1981 | 4,923 | | 1980 | 4,693 | | 1979 | 4,321 | | 1978 | 3,910 | | 1977 | 3,539 | | 1976 | 3,234 | | 1975 | 3,030 | | 1974 | 2,909 | | 1973 | 2,833 | | 1972 | 2,787 | | 1971 | 2,748 | | 1970 | 2,705 | | 1969 | 2,628 | | 1968 | 2,516 | | 1967 | 2,394 | | 1966 | 2,269 | | 1965 | 2,147 | | 1964 | 2,042 | | 1963 | 1,958 | | 1962 | 1,896 | | 1961 | 1,859 | | 1960 | 1,840 |
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