Year Percent 1999-01-01 0.069970000000000000 2000-01-01 0.084471000000000000 2001-01-01 0.092272000000000000 2002-01-01 0.067147000000000000 2003-01-01 0.065637000000000000 2004-01-01 0.073029000000000000 2005-01-01 0.061900000000000000 2006-01-01 0.050322000000000006 2007-01-01 0.051241999999999996 2008-01-01 0.048063999999999996 2009-01-01 0.049585000000000004 2010-01-01 0.043157999999999995 2011-01-01 0.039506000000000000 2012-01-01 0.039126000000000000 2013-01-01 0.044222000000000004 2014-01-01 0.044155000000000000 2015-01-01 0.050306000000000003 2016-01-01 0.061592999999999995