| Year | Value | | 2022 | 11,922 | | 2021 | 11,407 | | 2020 | 10,625 | | 2019 | 9,609 | | 2018 | 8,891 | | 2017 | 8,419 | | 2016 | 8,183 | | 2015 | 8,521 | | 2014 | 9,209 | | 2013 | 9,829 | | 2012 | 10,337 | | 2011 | 10,666 | | 2010 | 10,739 | | 2009 | 10,591 | | 2008 | 10,304 | | 2007 | 9,980 | | 2006 | 9,730 | | 2005 | 9,539 | | 2004 | 9,373 | | 2003 | 9,230 | | 2002 | 9,028 | | 2001 | 8,619 | | 2000 | 7,971 | | 1999 | 7,246 | | 1998 | 6,506 | | 1997 | 5,832 | | 1996 | 5,325 | | 1995 | 4,986 | | 1994 | 4,741 | | 1993 | 4,551 | | 1992 | 4,432 | | 1991 | 4,448 | | 1990 | 4,680 | | 1989 | 5,116 | | 1988 | 5,652 | | 1987 | 6,167 | | 1986 | 6,524 | | 1985 | 6,622 | | 1984 | 6,500 | | 1983 | 6,290 | | 1982 | 6,062 | | 1981 | 5,837 | | 1980 | 5,618 | | 1979 | 5,382 | | 1978 | 5,120 | | 1977 | 4,847 | | 1976 | 4,604 | | 1975 | 4,448 | | 1974 | 4,392 | | 1973 | 4,402 | | 1972 | 4,438 | | 1971 | 4,472 | | 1970 | 4,469 | | 1969 | 4,420 | | 1968 | 4,336 | | 1967 | 4,229 | | 1966 | 4,110 | | 1965 | 3,997 | | 1964 | 3,919 | | 1963 | 3,884 | | 1962 | 3,888 | | 1961 | 3,915 | | 1960 | 3,933 |
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