| Year | Value | | 2014 | 2,693.9727602251 | | 2013 | 2,498.3403574499 | | 2012 | 2,329.9258703834 | | 2011 | 2,289.1348486506 | | 2010 | 2,049.5445236545 | | 2009 | 1,833.0445606526 | | 2008 | 1,881.5372114844 | | 2007 | 1,829.976907681 | | 2006 | 1,769.1716745951 | | 2005 | 1,916.4790290455 | | 2004 | 1,814.4596597188 | | 2003 | 1,749.8638573022 | | 2002 | 1,653.3807211987 | | 2001 | 1,583.5598734846 | | 2000 | 1,574.3914041516 | | 1999 | 1,563.7959468795 | | 1998 | 1,517.8125589858 | | 1997 | 1,331.5208832912 | | 1996 | 1,150.7894896786 | | 1995 | 1,492.3604285528 | | 1994 | 1,988.5957127225 | | 1993 | 1,936.8369611696 | | 1992 | 2,125.1667179645 | | 1991 | 2,696.7058872185 | | 1990 | 3,039.1503540192 |
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