| Year | Value | | 2022 | 5,079 | | 2021 | 5,225 | | 2020 | 5,333 | | 2019 | 5,465 | | 2018 | 5,461 | | 2017 | 5,315 | | 2016 | 5,267 | | 2015 | 5,290 | | 2014 | 5,379 | | 2013 | 5,478 | | 2012 | 5,541 | | 2011 | 5,591 | | 2010 | 5,537 | | 2009 | 5,422 | | 2008 | 5,393 | | 2007 | 5,413 | | 2006 | 5,463 | | 2005 | 5,495 | | 2004 | 5,409 | | 2003 | 5,245 | | 2002 | 5,020 | | 2001 | 4,856 | | 2000 | 4,911 | | 1999 | 5,048 | | 1998 | 5,187 | | 1997 | 5,246 | | 1996 | 5,213 | | 1995 | 5,188 | | 1994 | 5,220 | | 1993 | 5,299 | | 1992 | 5,402 | | 1991 | 5,554 | | 1990 | 5,763 | | 1989 | 6,054 | | 1988 | 6,429 | | 1987 | 6,841 | | 1986 | 7,248 | | 1985 | 7,609 | | 1984 | 7,903 | | 1983 | 8,164 | | 1982 | 8,369 | | 1981 | 8,517 | | 1980 | 8,683 | | 1979 | 8,823 | | 1978 | 8,939 | | 1977 | 9,021 | | 1976 | 8,959 | | 1975 | 8,817 | | 1974 | 8,597 | | 1973 | 8,313 | | 1972 | 8,117 | | 1971 | 7,843 | | 1970 | 7,491 | | 1969 | 7,223 | | 1968 | 7,005 | | 1967 | 6,837 | | 1966 | 6,723 | | 1965 | 6,601 | | 1964 | 6,410 | | 1963 | 6,162 | | 1962 | 5,871 | | 1961 | 5,580 | | 1960 | 5,391 |
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