Year Percent 1996-01-01 9.3920200000000000 1997-01-01 7.5311500000000000 1998-01-01 4.4750900000000000 1999-01-01 9.5799899999999990 2000-01-01 9.4650500000000000 2001-01-01 8.1918600000000000 2002-01-01 6.7406100000000000 2003-01-01 6.3995800000000000 2004-01-01 7.6696100000000005 2005-01-01 6.1531100000000000 2006-01-01 5.5599200000000000 2007-01-01 5.2418500000000000 2008-01-01 4.9552600000000000 2009-01-01 4.2147600000000000 2010-01-01 5.2011800000000000 2011-01-01 4.9012500000000000 2012-01-01 3.9815199999999997 2013-01-01 3.3370500000000000 2014-01-01 2.7734900000000002 2015-01-01 2.0471800000000000 2016-01-01 3.9116300000000000