Year Percent 2003-01-01 74.9175975355429 2004-01-01 73.5024897968169 2005-01-01 75.1616338523932 2006-01-01 75.3698227364998 2007-01-01 75.9872422261007 2008-01-01 75.0080911530521 2009-01-01 72.0972483932026 2010-01-01 71.6130993531697 2011-01-01 71.6465864455394 2012-01-01 72.6878860670396 2013-01-01 73.6874443995818