Year Number 2007-01-01 569.9361 2008-01-01 675.5145 2009-01-01 595.2530 2010-01-01 533.0039 2011-01-01 470.5701 2012-01-01 468.8757 2013-01-01 441.7506 2014-01-01 449.6531 2015-01-01 478.1863 2016-01-01 469.1183 2017-01-01 484.7460