Year Percent 2010-01-01 4.80728249485859 2011-01-01 4.40674083290776 2012-01-01 4.48393991515183 2013-01-01 4.74668856049921 2014-01-01 4.82930334839711 2015-01-01 4.80018025793267 2016-01-01 4.91871057443227 2017-01-01 4.79711429962630