| Year | Value | | 2022 | 13,622 | | 2021 | 13,525 | | 2020 | 13,498 | | 2019 | 13,541 | | 2018 | 13,608 | | 2017 | 13,669 | | 2016 | 13,694 | | 2015 | 13,628 | | 2014 | 13,458 | | 2013 | 13,214 | | 2012 | 12,902 | | 2011 | 12,535 | | 2010 | 12,132 | | 2009 | 11,728 | | 2008 | 11,332 | | 2007 | 10,920 | | 2006 | 10,496 | | 2005 | 10,076 | | 2004 | 9,675 | | 2003 | 9,242 | | 2002 | 8,771 | | 2001 | 8,352 | | 2000 | 8,006 | | 1999 | 7,734 | | 1998 | 7,588 | | 1997 | 7,550 | | 1996 | 7,525 | | 1995 | 7,483 | | 1994 | 7,426 | | 1993 | 7,353 | | 1992 | 7,265 | | 1991 | 7,156 | | 1990 | 7,025 | | 1989 | 6,894 | | 1988 | 6,767 | | 1987 | 6,629 | | 1986 | 6,486 | | 1985 | 6,335 | | 1984 | 6,173 | | 1983 | 6,002 | | 1982 | 5,823 | | 1981 | 5,637 | | 1980 | 5,445 | | 1979 | 5,113 | | 1978 | 4,744 | | 1977 | 4,525 | | 1976 | 4,358 | | 1975 | 4,199 | | 1974 | 4,046 | | 1973 | 3,905 | | 1972 | 3,769 | | 1971 | 3,636 | | 1970 | 3,519 | | 1969 | 3,411 | | 1968 | 3,309 | | 1967 | 3,221 | | 1966 | 3,148 | | 1965 | 3,077 | | 1964 | 3,008 | | 1963 | 2,939 | | 1962 | 2,867 | | 1961 | 2,791 | | 1960 | 2,711 |
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