| Year | Value | | 2014 | 1,486.2458307051 | | 2013 | 1,676.7425254498 | | 2012 | 1,743.0032896862 | | 2011 | 1,790.9215358764 | | 2010 | 1,869.773447905 | | 2009 | 1,884.5576866121 | | 2008 | 1,916.548105453 | | 2007 | 2,036.8953219156 | | 2006 | 2,096.9428333341 | | 2005 | 2,106.176158819 | | 2004 | 2,116.0959147821 | | 2003 | 2,096.6679315614 | | 2002 | 2,102.9524951638 | | 2001 | 2,113.0287838148 | | 2000 | 2,142.0379856649 | | 1999 | 2,162.9952993466 | | 1998 | 2,042.2930399777 | | 1997 | 1,986.5723273679 | | 1996 | 2,256.1137252303 | | 1995 | 2,343.5758217348 | | 1994 | 2,468.300702637 | | 1993 | 2,513.7264188397 | | 1992 | 2,909.0160757879 | | 1991 | 3,110.5198309812 | | 1990 | 3,275.4630056886 |
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