Year Percent 2000-01-01 47.475 2001-01-01 46.150 2002-01-01 44.400 2003-01-01 44.000 2004-01-01 44.350 2005-01-01 45.150 2006-01-01 46.525 2007-01-01 48.575 2008-01-01 50.375 2009-01-01 50.425 2010-01-01 49.975 2011-01-01 50.200 2012-01-01 50.250 2013-01-01 50.150 2014-01-01 51.200 2015-01-01 51.925 2016-01-01 52.750 2017-01-01 53.700