Year Percent 1991-01-01 0.25255300000000000 1992-01-01 0.23718400000000000 1993-01-01 0.23568200000000000 1994-01-01 0.26457300000000000 1995-01-01 0.30209700000000000 1996-01-01 0.35211400000000000 1997-01-01 0.32115800000000000 1998-01-01 0.35658400000000000 1999-01-01 0.34096100000000000 2000-01-01 0.35238900000000000 2001-01-01 0.34833400000000003 2002-01-01 0.46867400000000000 2003-01-01 0.46050200000000000 2004-01-01 0.43607200000000000 2005-01-01 0.45684500000000000 2006-01-01 0.43647800000000000 2007-01-01 0.45187500000000000 2008-01-01 0.47228600000000000 2009-01-01 0.44725299999999996 2010-01-01 0.54469200000000000 2011-01-01 0.52459899999999990 2012-01-01 0.51240700000000000 2013-01-01 0.53104700000000000 2014-01-01 0.55512100000000000 2015-01-01 0.53636400000000010 2016-01-01 0.62791800000000000