Year Percent 1991-01-01 65.3939971923828 1992-01-01 65.4960021972656 1993-01-01 65.6409988403320 1994-01-01 66.3359985351563 1995-01-01 67.1129989624023 1996-01-01 63.8769989013672 1997-01-01 65.8820037841797 1998-01-01 65.9889984130859 1999-01-01 63.1969985961914 2000-01-01 64.5169982910156 2001-01-01 64.6039962768555 2002-01-01 63.4339981079102 2003-01-01 65.3280029296875 2004-01-01 65.6309967041016 2005-01-01 66.9160003662109 2006-01-01 66.6869964599609 2007-01-01 67.1930007934570 2008-01-01 67.4889984130859 2009-01-01 67.1869964599609 2010-01-01 65.8300018310547 2011-01-01 66.0169982910156 2012-01-01 69.3929977416992 2013-01-01 68.1589965820313 2014-01-01 66.0360031127930 2015-01-01 66.4010009765625 2016-01-01 66.6179962158203 2017-01-01 67.1620025634766