Year Percent 2003-01-01 7.13615311458628 2004-01-01 4.13663213144748 2005-01-01 2.28194607024302 2006-01-01 4.96116689278764 2007-01-01 6.54788141133041 2008-01-01 9.09464307167043 2009-01-01 9.45172651530944 2010-01-01 4.87491987645650 2011-01-01 5.00559518073203 2012-01-01 6.72199777331876 2013-01-01 5.60092502322356 2014-01-01 5.34952612720511 2015-01-01 3.39566065540327 2016-01-01 6.72779540721608 2017-01-01 6.14392366175068