Year Percent 2008-01-01 6.74012 2009-01-01 3.71611 2010-01-01 4.54354 2011-01-01 4.01513 2012-01-01 99.82420 2013-01-01 16.48580 2014-01-01 15.68510 2015-01-01 16.60270 2016-01-01 28.68460