Year Percent 2006-01-01 20.9000 2007-01-01 16.0000 2008-01-01 13.9000 2009-01-01 28.3000 2010-01-01 26.2010 2011-01-01 26.4376 2012-01-01 27.3736 2013-01-01 30.1277 2014-01-01 34.1704 2015-01-01 37.1356 2016-01-01 40.1321