Year Number 2005-01-01 13.8254 2006-01-01 22.2680 2007-01-01 34.2699 2008-01-01 41.2424 2009-01-01 45.0790 2010-01-01 47.3775 2011-01-01 47.1947 2012-01-01 46.5983 2013-01-01 44.8905 2014-01-01 44.3566 2015-01-01 45.7485 2016-01-01 50.6643 2017-01-01 45.6030