Year Percent 1996-01-01 2.9838800000000000 1997-01-01 2.5196099999999997 1998-01-01 2.2666900000000000 1999-01-01 1.8918099999999998 2000-01-01 2.0594099999999997 2001-01-01 2.1899400000000000 2002-01-01 1.3761700000000001 2003-01-01 1.6752300000000000 2004-01-01 2.5266200000000000 2005-01-01 3.8176500000000000 2006-01-01 2.3615700000000000 2007-01-01 2.1358900000000003 2008-01-01 1.8531099999999998 2009-01-01 1.6503500000000000 2010-01-01 1.5674700000000001 2011-01-01 1.4324400000000000 2012-01-01 1.4466400000000000 2013-01-01 1.2996500000000000 2014-01-01 1.3251300000000000 2015-01-01 1.1260600000000000 2016-01-01 1.1485700000000000