Year Percent 2002-01-01 18.0285 2003-01-01 17.5719 2004-01-01 14.3662 2005-01-01 15.0078 2006-01-01 17.1421 2007-01-01 13.3364 2008-01-01 10.4174 2009-01-01 26.3946 2010-01-01 27.0486 2011-01-01 22.0424 2012-01-01 25.6388 2013-01-01 28.1714 2014-01-01 26.8342 2015-01-01 31.4991 2016-01-01 45.9361