Year Percent 1996-01-01 25.566300000000000 1997-01-01 19.240000000000000 1998-01-01 10.222999999999999 1999-01-01 21.727100000000000 2000-01-01 24.439300000000000 2001-01-01 21.986600000000000 2002-01-01 16.882700000000000 2003-01-01 32.388700000000000 2004-01-01 40.972300000000000 2005-01-01 45.051800000000000 2006-01-01 52.931900000000000 2007-01-01 47.160600000000000 2008-01-01 42.112600000000000 2009-01-01 47.703400000000000 2010-01-01 39.922300000000000 2011-01-01 41.301900000000000 2012-01-01 38.874400000000000 2013-01-01 47.475200000000000 2014-01-01 48.494400000000000 2015-01-01 30.724200000000000 2016-01-01 24.092700000000000