Year Percent 1996-01-01 4.2159400000000000 1997-01-01 4.1162100000000000 1998-01-01 4.8596800000000000 1999-01-01 4.7157599999999995 2000-01-01 5.1812000000000000 2001-01-01 5.3278500000000000 2002-01-01 6.0573800000000000 2003-01-01 6.6448899999999990 2004-01-01 5.5684600000000000 2005-01-01 6.1371100000000000 2006-01-01 6.6245100000000010 2007-01-01 6.1745600000000000 2008-01-01 5.9141400000000000 2009-01-01 6.3201900000000000 2010-01-01 5.5453700000000000 2011-01-01 6.0715300000000000 2012-01-01 5.4624600000000000 2013-01-01 6.0535900000000000 2014-01-01 4.2540100000000000 2015-01-01 4.5493000000000000 2016-01-01 3.8729600000000000