Year Percent 1996-01-01 16.0816000000000000 1997-01-01 12.0888000000000000 1998-01-01 11.0040000000000010 1999-01-01 6.4917300000000004 2000-01-01 10.6003000000000000 2001-01-01 10.3429000000000000 2002-01-01 12.1202000000000000 2003-01-01 10.9231000000000000 2004-01-01 7.5330100000000010 2005-01-01 7.3018100000000010 2006-01-01 6.8312000000000000 2007-01-01 7.0890500000000000 2008-01-01 7.1992000000000000 2009-01-01 6.8479700000000000 2010-01-01 6.6485000000000000 2011-01-01 8.9723000000000000 2012-01-01 8.8750800000000000 2013-01-01 7.7021200000000000 2014-01-01 7.1244000000000000 2015-01-01 6.8402199999999995 2016-01-01 5.6015800000000000