Year Percent 2006-01-01 4.40000 2007-01-01 2.30000 2008-01-01 2.00000 2009-01-01 3.80000 2010-01-01 5.46606 2011-01-01 8.12278 2012-01-01 9.00887 2013-01-01 9.22148 2014-01-01 7.98988 2015-01-01 7.58752 2016-01-01 6.75218