Year Percent 2001-01-01 4.0159400000000005 2002-01-01 7.4385699999999995 2003-01-01 6.8130600000000010 2004-01-01 5.9919000000000000 2005-01-01 4.7639300000000000 2006-01-01 8.3854600000000000 2007-01-01 10.5478000000000000 2008-01-01 10.4680000000000000 2009-01-01 9.2072800000000000 2010-01-01 5.9986800000000000 2011-01-01 5.5793700000000000 2012-01-01 4.8806300000000000 2013-01-01 3.9118699999999995 2014-01-01 3.3833699999999998 2015-01-01 3.4357599999999997 2016-01-01 4.7631100000000000 2017-01-01 4.6289099999999990