| Year | Value | | 2022 | 14,294 | | 2021 | 13,978 | | 2020 | 13,940 | | 2019 | 13,837 | | 2018 | 13,317 | | 2017 | 12,451 | | 2016 | 11,688 | | 2015 | 11,233 | | 2014 | 10,887 | | 2013 | 10,764 | | 2012 | 10,952 | | 2011 | 11,140 | | 2010 | 11,186 | | 2009 | 11,411 | | 2008 | 11,575 | | 2007 | 11,289 | | 2006 | 10,809 | | 2005 | 10,527 | | 2004 | 10,505 | | 2003 | 10,608 | | 2002 | 10,772 | | 2001 | 10,803 | | 2000 | 10,707 | | 1999 | 10,707 | | 1998 | 10,676 | | 1997 | 10,606 | | 1996 | 10,625 | | 1995 | 10,562 | | 1994 | 10,404 | | 1993 | 10,310 | | 1992 | 10,175 | | 1991 | 9,885 | | 1990 | 9,693 | | 1989 | 9,577 | | 1988 | 9,302 | | 1987 | 8,997 | | 1986 | 8,790 | | 1985 | 8,543 | | 1984 | 8,215 | | 1983 | 7,873 | | 1982 | 7,503 | | 1981 | 7,102 | | 1980 | 6,644 | | 1979 | 6,202 | | 1978 | 5,867 | | 1977 | 5,634 | | 1976 | 5,498 | | 1975 | 5,472 | | 1974 | 5,478 | | 1973 | 5,488 | | 1972 | 5,528 | | 1971 | 5,638 | | 1970 | 5,845 | | 1969 | 6,030 | | 1968 | 6,133 | | 1967 | 6,146 | | 1966 | 6,049 | | 1965 | 5,911 | | 1964 | 5,802 | | 1963 | 5,717 | | 1962 | 5,631 | | 1961 | 5,599 | | 1960 | 5,622 |
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