Year Number 2004-01-01 56.8495 2005-01-01 59.7774 2006-01-01 60.8664 2007-01-01 59.9404 2008-01-01 59.9431 2009-01-01 59.1981 2010-01-01 59.4578 2011-01-01 66.9690 2012-01-01 67.9264 2013-01-01 62.1887 2014-01-01 61.2411 2015-01-01 58.6227 2016-01-01 56.8864