Year Number 2004-01-01 40.4259 2005-01-01 48.9715 2006-01-01 50.7303 2007-01-01 49.0656 2008-01-01 50.3517 2009-01-01 39.9562 2010-01-01 35.4282 2011-01-01 31.0719 2012-01-01 29.1943 2013-01-01 27.9054 2014-01-01 27.3423 2015-01-01 26.1335 2016-01-01 27.0778