| Year | Value | | 2014 | 15,249.98938023 | | 2013 | 15,510.835503474 | | 2012 | 15,689.223307624 | | 2011 | 15,710.973759305 | | 2010 | 16,484.094275371 | | 2009 | 15,243.110387945 | | 2008 | 16,349.233325034 | | 2007 | 17,160.863119999 | | 2006 | 17,215.037290164 | | 2005 | 16,117.890332163 | | 2004 | 16,777.565849019 | | 2003 | 16,445.572561286 | | 2002 | 16,140.066969222 | | 2001 | 15,709.883253842 | | 2000 | 15,305.409808607 | | 1999 | 15,075.867190504 | | 1998 | 14,846.420819412 | | 1997 | 14,454.938728578 | | 1996 | 13,721.923758331 | | 1995 | 13,591.396670576 | | 1994 | 13,603.276357896 | | 1993 | 13,012.669430866 | | 1992 | 12,514.10156938 | | 1991 | 12,470.730432771 | | 1990 | 12,485.683648285 | | 1989 | 12,034.757273379 | | 1988 | 11,778.272270732 | | 1987 | 11,358.394752118 | | 1986 | 10,622.888181216 | | 1985 | 10,482.831606832 | | 1984 | 9,808.4662572414 | | 1983 | 9,124.1646307797 | | 1982 | 8,533.1617405918 | | 1981 | 8,493.6053687069 | | 1980 | 8,295.7860963462 | | 1979 | 7,930.6313737095 | | 1978 | 7,330.4144657328 | | 1977 | 6,726.6636870735 | | 1976 | 6,545.7467987567 | | 1975 | 5,946.3773283752 | | 1974 | 6,140.1866807772 | | 1973 | 6,046.8303057748 | | 1972 | 5,516.1405250431 | | 1971 | 4,889.5042717845 | | 1970 | 4,570.9068023473 | | 1969 | 4,071.5560952769 | | 1968 | 3,628.685288932 | | 1967 | 3,345.387846133 | | 1966 | 3,197.8648592658 | | 1965 | 2,938.3846378359 | | 1964 | 2,715.3750112948 | | 1963 | 2,479.1585098431 | | 1962 | 2,389.2098819912 | | 1961 | 2,187.6236408612 | | 1960 | 1,873.2924661496 |
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