Year Number 2004-01-01 0.3017 2005-01-01 0.3691 2006-01-01 0.3793 2007-01-01 0.4413 2008-01-01 0.4307 2009-01-01 0.4202 2010-01-01 0.4753 2011-01-01 0.4961 2012-01-01 0.5308 2013-01-01 0.8980 2014-01-01 0.9486 2015-01-01 0.8941 2016-01-01 1.9911