Year Percent 2005-01-01 4.61792318043976 2006-01-01 3.69606922548464 2007-01-01 3.39077458542386 2008-01-01 3.70112207184760 2009-01-01 4.93940194635992 2010-01-01 3.98503121277985 2011-01-01 3.42239089210246 2012-01-01 3.03665011118982 2013-01-01 2.96364802477270 2014-01-01 3.39599488178663 2015-01-01 3.26020837223814 2016-01-01 3.45881408369160 2017-01-01 3.57110034713861