Year Number 2004-01-01 1.1215 2005-01-01 1.1730 2006-01-01 1.1798 2007-01-01 1.3654 2008-01-01 2.0113 2009-01-01 2.3237 2010-01-01 2.4180 2011-01-01 2.3467 2012-01-01 2.6434 2013-01-01 2.8310 2014-01-01 2.9151 2015-01-01 2.9013 2016-01-01 2.7711