Year Number 2004-01-01 0.3087 2005-01-01 0.3443 2006-01-01 0.3622 2007-01-01 0.3779 2008-01-01 0.4021 2009-01-01 0.5092 2010-01-01 0.6938 2011-01-01 1.2505 2012-01-01 2.8643 2013-01-01 1.2745 2014-01-01 1.5141 2015-01-01 1.8939 2016-01-01 4.9812