Year Percent 1990-01-01 0.38236700000000000 1991-01-01 0.42797700000000005 1992-01-01 0.47925400000000000 1993-01-01 0.44133999999999995 1994-01-01 0.43388900000000000 1995-01-01 0.40952700000000000 1996-01-01 0.43865800000000000 1997-01-01 0.45975699999999997 1998-01-01 0.44171900000000000 1999-01-01 0.44869000000000000 2000-01-01 0.45293800000000000 2001-01-01 0.42954100000000000 2002-01-01 0.46566300000000000 2003-01-01 0.50293000000000000 2004-01-01 0.50612100000000000 2005-01-01 0.47329700000000000 2006-01-01 0.42235700000000000 2007-01-01 0.46457800000000000 2008-01-01 0.43749899999999997 2009-01-01 0.40152100000000000 2010-01-01 0.38402400000000000 2011-01-01 0.40671799999999997 2012-01-01 0.45218000000000000 2013-01-01 0.47824200000000000 2014-01-01 0.48251499999999997 2015-01-01 0.47448800000000000 2016-01-01 0.49133900000000000