Year Percent 1996-01-01 2.5553200000000000 1997-01-01 2.0924099999999997 1998-01-01 1.9718300000000000 1999-01-01 1.7511100000000000 2000-01-01 1.6979700000000000 2001-01-01 1.5694500000000000 2002-01-01 1.8168000000000000 2003-01-01 1.6552500000000000 2004-01-01 1.5524000000000000 2005-01-01 1.5016800000000000 2006-01-01 1.6491099999999999 2007-01-01 1.6406000000000000 2008-01-01 1.6710500000000000 2009-01-01 1.5680300000000000 2010-01-01 1.4667000000000000 2011-01-01 1.4390600000000000 2012-01-01 1.4943000000000000 2013-01-01 1.4594200000000002 2014-01-01 1.4532900000000000 2015-01-01 1.4340600000000001 2016-01-01 1.6187000000000000