Year Percent 1994-01-01 58.318000000000005 1995-01-01 64.339200000000000 1996-01-01 72.064100000000000 1997-01-01 66.477900000000000 1998-01-01 58.455800000000000 1999-01-01 64.528400000000000 2000-01-01 68.710600000000000 2001-01-01 70.185200000000000 2002-01-01 71.626400000000000 2003-01-01 73.590900000000000 2004-01-01 77.852100000000000 2005-01-01 81.264500000000000 2006-01-01 84.102600000000000 2007-01-01 86.557999999999990 2008-01-01 88.002400000000000 2009-01-01 88.984200000000000 2010-01-01 90.580800000000000 2011-01-01 92.065900000000000 2012-01-01 92.370700000000000 2013-01-01 92.506100000000000 2014-01-01 92.486700000000000 2015-01-01 92.039500000000000 2016-01-01 92.879600000000000