| Year | Value | | 2022 | 15,768 | | 2021 | 15,253 | | 2020 | 14,287 | | 2019 | 12,984 | | 2018 | 12,095 | | 2017 | 11,572 | | 2016 | 11,342 | | 2015 | 11,800 | | 2014 | 12,652 | | 2013 | 13,347 | | 2012 | 13,888 | | 2011 | 14,221 | | 2010 | 14,198 | | 2009 | 13,864 | | 2008 | 13,431 | | 2007 | 13,029 | | 2006 | 12,739 | | 2005 | 12,570 | | 2004 | 12,472 | | 2003 | 12,363 | | 2002 | 12,096 | | 2001 | 11,531 | | 2000 | 10,645 | | 1999 | 9,615 | | 1998 | 8,546 | | 1997 | 7,623 | | 1996 | 7,039 | | 1995 | 6,774 | | 1994 | 6,699 | | 1993 | 6,701 | | 1992 | 6,730 | | 1991 | 6,834 | | 1990 | 7,098 | | 1989 | 7,555 | | 1988 | 8,111 | | 1987 | 8,656 | | 1986 | 9,057 | | 1985 | 9,183 | | 1984 | 9,029 | | 1983 | 8,703 | | 1982 | 8,289 | | 1981 | 7,831 | | 1980 | 7,367 | | 1979 | 6,922 | | 1978 | 6,509 | | 1977 | 6,157 | | 1976 | 5,917 | | 1975 | 5,834 | | 1974 | 5,890 | | 1973 | 6,021 | | 1972 | 6,170 | | 1971 | 6,289 | | 1970 | 6,345 | | 1969 | 6,324 | | 1968 | 6,236 | | 1967 | 6,114 | | 1966 | 5,978 | | 1965 | 5,857 | | 1964 | 5,775 | | 1963 | 5,720 | | 1962 | 5,666 | | 1961 | 5,590 | | 1960 | 5,471 |
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