Year Percent 2006-01-01 4.22287482692692 2007-01-01 4.33029584603127 2008-01-01 4.79434301279048 2009-01-01 6.30588702013429 2010-01-01 5.28451004353841 2011-01-01 4.30134935041380 2012-01-01 3.95271392476598 2013-01-01 4.16017363089601 2014-01-01 4.79673835847353