Year Percent 2005-01-01 2.69 2006-01-01 2.32 2007-01-01 2.13 2008-01-01 1.92 2009-01-01 2.10 2010-01-01 1.70 2011-01-01 1.63 2012-01-01 1.64 2013-01-01 1.78 2014-01-01 1.95 2015-01-01 1.95 2016-01-01 2.17