Year Percent 1997-01-01 1.0216700000000000 1998-01-01 1.1886900000000000 1999-01-01 5.3193600000000000 2000-01-01 6.6278399999999990 2001-01-01 6.1149900000000000 2002-01-01 5.5363500000000000 2003-01-01 4.8930500000000000 2004-01-01 4.8334500000000000 2005-01-01 5.5017600000000000 2006-01-01 4.3883600000000000 2007-01-01 5.2409900000000000 2008-01-01 5.7553100000000000 2009-01-01 5.8908000000000000 2010-01-01 5.4060500000000000 2011-01-01 5.4963200000000000 2012-01-01 5.4349700000000000 2013-01-01 5.1161400000000010 2014-01-01 5.1001900000000004 2015-01-01 4.5359099999999990 2016-01-01 4.2701300000000000