| Year | Value | | 2022 | 5,647 | | 2021 | 5,733 | | 2020 | 5,705 | | 2019 | 5,570 | | 2018 | 5,346 | | 2017 | 5,169 | | 2016 | 5,138 | | 2015 | 5,125 | | 2014 | 5,098 | | 2013 | 5,075 | | 2012 | 5,027 | | 2011 | 4,994 | | 2010 | 4,953 | | 2009 | 4,897 | | 2008 | 4,830 | | 2007 | 4,771 | | 2006 | 4,737 | | 2005 | 4,718 | | 2004 | 4,670 | | 2003 | 4,579 | | 2002 | 4,458 | | 2001 | 4,348 | | 2000 | 4,282 | | 1999 | 4,253 | | 1998 | 4,296 | | 1997 | 4,420 | | 1996 | 4,620 | | 1995 | 4,877 | | 1994 | 5,155 | | 1993 | 5,462 | | 1992 | 5,801 | | 1991 | 6,112 | | 1990 | 6,283 | | 1989 | 6,329 | | 1988 | 6,253 | | 1987 | 6,120 | | 1986 | 6,047 | | 1985 | 5,941 | | 1984 | 5,724 | | 1983 | 5,475 | | 1982 | 5,282 | | 1981 | 5,145 | | 1980 | 5,030 | | 1979 | 4,948 | | 1978 | 4,911 | | 1977 | 4,936 | | 1976 | 5,046 | | 1975 | 5,115 | | 1974 | 5,117 | | 1973 | 5,164 | | 1972 | 5,252 | | 1971 | 5,318 | | 1970 | 5,252 | | 1969 | 5,005 | | 1968 | 4,627 | | 1967 | 4,218 | | 1966 | 3,885 | | 1965 | 3,699 | | 1964 | 3,653 | | 1963 | 3,702 | | 1962 | 3,825 | | 1961 | 3,987 | | 1960 | 4,089 |
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