Year Percent 1996-01-01 62.475000000000000 1997-01-01 55.352500000000000 1998-01-01 51.141000000000005 1999-01-01 71.473500000000000 2000-01-01 59.509700000000000 2001-01-01 50.000000000000000 2002-01-01 67.071100000000000 2003-01-01 65.456500000000000 2004-01-01 63.890600000000000 2005-01-01 62.728100000000000 2006-01-01 60.477500000000000 2007-01-01 61.869300000000000 2008-01-01 69.903100000000000 2009-01-01 59.457100000000000 2010-01-01 57.470300000000000 2011-01-01 59.750100000000000 2012-01-01 58.907100000000000 2013-01-01 55.722500000000000 2014-01-01 60.298300000000000