Year Percent 1999-01-01 4.1966000000000000 2000-01-01 5.1086599999999995 2001-01-01 5.1133600000000000 2002-01-01 5.4019000000000000 2003-01-01 6.3792300000000010 2004-01-01 6.8418700000000000 2005-01-01 8.3229200000000000 2006-01-01 6.4256600000000000 2007-01-01 6.5263800000000005 2008-01-01 5.6153600000000000 2009-01-01 5.4022800000000000 2010-01-01 5.3807700000000000 2011-01-01 5.0007900000000000 2012-01-01 5.5790100000000000 2013-01-01 4.2246200000000000 2014-01-01 4.0421600000000000 2015-01-01 3.7207199999999996