Year Percent 2005-01-01 10.03067961156350 2006-01-01 9.33813145184062 2007-01-01 8.38370224903815 2008-01-01 8.19879228172122 2009-01-01 9.63580511503688 2010-01-01 10.22148936689380 2011-01-01 10.37192871128670 2012-01-01 11.47041377014330 2013-01-01 12.06643118554970 2014-01-01 11.78423488703250 2015-01-01 11.03607181365660 2016-01-01 10.36746664533890 2017-01-01 9.43708535562989