Year Percent 1995-01-01 23.699700000000000 1996-01-01 28.660999999999998 1997-01-01 31.546600000000000 1998-01-01 31.796200000000000 1999-01-01 29.168500000000000 2000-01-01 38.937600000000000 2001-01-01 47.064100000000000 2002-01-01 45.318200000000000 2003-01-01 54.028700000000000 2004-01-01 56.936500000000000 2005-01-01 51.727100000000000 2006-01-01 55.528900000000000 2007-01-01 53.549300000000000 2008-01-01 48.460100000000000 2009-01-01 57.283200000000000 2010-01-01 55.675300000000000 2011-01-01 40.062200000000000 2012-01-01 40.060400000000000 2013-01-01 44.358600000000000 2014-01-01 36.836800000000000 2015-01-01 33.331300000000000 2016-01-01 29.698100000000000