Year Percent 1996-01-01 2.9228099999999997 1997-01-01 3.4670900000000002 1998-01-01 3.1143900000000000 1999-01-01 3.0575799999999997 2000-01-01 4.6775000000000000 2001-01-01 6.7198699999999990 2002-01-01 3.8872500000000000 2003-01-01 3.5171900000000003 2004-01-01 3.1603900000000000 2005-01-01 2.8703700000000000 2006-01-01 2.6360900000000003 2007-01-01 2.6884099999999997 2008-01-01 2.2317200000000000 2009-01-01 2.1560500000000000 2010-01-01 2.2875500000000000 2011-01-01 2.1927500000000000 2012-01-01 2.4036800000000000 2013-01-01 2.2888599999999997 2014-01-01 2.1983000000000000 2015-01-01 2.0905900000000000 2016-01-01 2.1322300000000000