Year Percent 2004-01-01 4.4570000000000000 2005-01-01 4.5310000000000010 2006-01-01 4.1300000000000000 2007-01-01 4.3000000000000000 2008-01-01 4.7028099999999995 2009-01-01 4.8669500000000000 2010-01-01 5.0969400000000000 2011-01-01 5.1460000000000000 2012-01-01 5.2978000000000000 2013-01-01 5.2000000000000000 2014-01-01 5.2000000000000000 2015-01-01 5.2100000000000000 2016-01-01 5.2360000000000010