| Year | Value | | 2022 | 14,880 | | 2021 | 14,199 | | 2020 | 13,752 | | 2019 | 13,440 | | 2018 | 13,160 | | 2017 | 12,924 | | 2016 | 12,557 | | 2015 | 12,085 | | 2014 | 11,482 | | 2013 | 10,904 | | 2012 | 10,425 | | 2011 | 9,910 | | 2010 | 9,543 | | 2009 | 9,405 | | 2008 | 9,229 | | 2007 | 9,071 | | 2006 | 9,051 | | 2005 | 9,020 | | 2004 | 8,838 | | 2003 | 8,700 | | 2002 | 8,647 | | 2001 | 8,666 | | 2000 | 8,898 | | 1999 | 9,209 | | 1998 | 9,406 | | 1997 | 9,491 | | 1996 | 9,393 | | 1995 | 9,048 | | 1994 | 8,479 | | 1993 | 7,883 | | 1992 | 7,307 | | 1991 | 6,815 | | 1990 | 6,575 | | 1989 | 6,436 | | 1988 | 6,217 | | 1987 | 6,012 | | 1986 | 5,885 | | 1985 | 5,797 | | 1984 | 5,907 | | 1983 | 6,240 | | 1982 | 6,681 | | 1981 | 7,061 | | 1980 | 7,352 | | 1979 | 7,520 | | 1978 | 7,633 | | 1977 | 7,770 | | 1976 | 7,869 | | 1975 | 7,868 | | 1974 | 7,768 | | 1973 | 7,655 | | 1972 | 7,552 | | 1971 | 7,531 | | 1970 | 7,531 | | 1969 | 7,437 | | 1968 | 7,321 | | 1967 | 7,218 | | 1966 | 7,019 | | 1965 | 6,752 | | 1964 | 6,536 | | 1963 | 6,380 | | 1962 | 6,238 | | 1961 | 6,078 | | 1960 | 5,923 |
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