| Year | Value | | 2014 | 3,493.1768951801 | | 2013 | 3,523.3807432259 | | 2012 | 3,214.414336933 | | 2011 | 3,214.7294375039 | | 2010 | 2,887.8552593027 | | 2009 | 2,931.5520558828 | | 2008 | 2,936.6705497642 | | 2007 | 2,680.1983536195 | | 2006 | 2,674.2116726658 | | 2005 | 2,675.2159931812 | | 2004 | 2,506.9921578152 | | 2003 | 2,399.8570804716 | | 2002 | 2,475.4572635605 | | 2001 | 2,306.1424637973 | | 2000 | 2,227.5667121783 |
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