Year Percent 2000-01-01 68.5493587094797 2001-01-01 69.7385273682356 2002-01-01 72.1880247484643 2003-01-01 70.8153787637467 2004-01-01 71.8321281285127 2005-01-01 72.2611208856033 2006-01-01 72.6828368578062 2007-01-01 74.7638501113337 2008-01-01 74.3042106760778 2009-01-01 74.3374570234991 2010-01-01 75.0119361143210 2011-01-01 76.5424517617836 2012-01-01 77.1756837223699 2013-01-01 78.1769618522986 2014-01-01 79.6654077170319 2015-01-01 79.0792394646653 2016-01-01 79.0851739467344 2017-01-01 80.4180920600041