Year Percent 1993-01-01 0.55498800000000000 1994-01-01 0.59615100000000000 1995-01-01 0.63618900000000000 1996-01-01 0.57228000000000000 1997-01-01 0.50762500000000000 1998-01-01 0.46619799999999995 1999-01-01 0.44745300000000000 2000-01-01 0.40696800000000000 2001-01-01 0.39304700000000000 2002-01-01 0.40242900000000000 2003-01-01 0.45579400000000000 2004-01-01 0.49813800000000000 2005-01-01 0.50130400000000000 2006-01-01 0.43209899999999996 2007-01-01 0.40720900000000000 2008-01-01 0.42153300000000000 2009-01-01 0.41554399999999997 2010-01-01 0.39442200000000000 2011-01-01 0.37554499999999996 2012-01-01 0.35688100000000000 2013-01-01 0.32950300000000005 2014-01-01 0.27057600000000004 2015-01-01 0.28377300000000000 2016-01-01 0.31765000000000000