| Year | Value | | 2022 | 18,033 | | 2021 | 17,192 | | 2020 | 16,412 | | 2019 | 15,699 | | 2018 | 15,048 | | 2017 | 14,483 | | 2016 | 14,052 | | 2015 | 13,762 | | 2014 | 13,588 | | 2013 | 13,520 | | 2012 | 13,550 | | 2011 | 13,635 | | 2010 | 13,716 | | 2009 | 13,763 | | 2008 | 13,729 | | 2007 | 13,570 | | 2006 | 13,287 | | 2005 | 12,870 | | 2004 | 12,332 | | 2003 | 11,730 | | 2002 | 11,111 | | 2001 | 10,488 | | 2000 | 9,871 | | 1999 | 9,293 | | 1998 | 8,735 | | 1997 | 8,164 | | 1996 | 7,603 | | 1995 | 7,067 | | 1994 | 6,564 | | 1993 | 6,107 | | 1992 | 5,716 | | 1991 | 5,413 | | 1990 | 5,214 | | 1989 | 5,119 | | 1988 | 5,104 | | 1987 | 5,143 | | 1986 | 5,221 | | 1985 | 5,333 | | 1984 | 5,468 | | 1983 | 5,619 | | 1982 | 5,775 | | 1981 | 5,928 | | 1980 | 6,044 | | 1979 | 6,124 | | 1978 | 6,191 | | 1977 | 6,239 | | 1976 | 6,271 | | 1975 | 6,272 | | 1974 | 6,256 | | 1973 | 6,234 | | 1972 | 6,190 | | 1971 | 6,120 | | 1970 | 6,018 | | 1969 | 5,869 | | 1968 | 5,690 | | 1967 | 5,510 | | 1966 | 5,340 | | 1965 | 5,191 | | 1964 | 5,058 | | 1963 | 4,948 | | 1962 | 4,863 | | 1961 | 4,814 | | 1960 | 4,802 |
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