Year Number 2008-01-01 392.8272 2009-01-01 392.6458 2010-01-01 376.4237 2011-01-01 355.9690 2012-01-01 356.5532 2013-01-01 342.3797 2014-01-01 327.3265 2015-01-01 327.5053 2016-01-01 327.6477 2017-01-01 330.1748