Year Number 2007-01-01 10.9981 2008-01-01 11.7197 2009-01-01 11.8354 2010-01-01 12.1083 2011-01-01 12.9490 2012-01-01 13.0800 2013-01-01 13.1550 2014-01-01 13.2089 2015-01-01 13.8530 2016-01-01 13.9185 2017-01-01 13.2198