| Year | Value | | 2014 | 5,374.9013088917 | | 2013 | 5,460.2626302233 | | 2012 | 5,520.4876242695 | | 2011 | 5,486.9935469596 | | 2010 | 5,526.0020194962 | | 2009 | 5,293.1647592824 | | 2008 | 5,581.2712313984 | | 2007 | 5,550.2626567901 | | 2006 | 5,489.984674606 | | 2005 | 5,374.5312384423 | | 2004 | 5,295.3534211598 | | 2003 | 5,188.6733590578 | | 2002 | 5,074.6017448446 | | 2001 | 5,028.5244451245 | | 2000 | 4,937.5355664624 | | 1999 | 4,809.137146143 | | 1998 | 4,739.042208368 | | 1997 | 4,697.9942535636 | | 1996 | 4,688.8479842829 | | 1995 | 4,644.8433710061 | | 1994 | 4,598.621190212 | | 1993 | 4,711.7790567994 | | 1992 | 4,866.1340228025 | | 1991 | 5,019.7558735188 | | 1990 | 5,055.4775945366 |
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