Year Percent 1996-01-01 68.8031 1997-01-01 64.7452 1998-01-01 69.5714 1999-01-01 69.6132 2000-01-01 62.8111 2001-01-01 70.3880 2002-01-01 69.6553 2003-01-01 70.5842 2004-01-01 67.4421 2005-01-01 67.4865 2006-01-01 67.0046 2007-01-01 69.3621 2008-01-01 68.8508 2009-01-01 73.4947 2010-01-01 73.4863 2011-01-01 73.2056 2012-01-01 71.6688 2013-01-01 68.9452 2014-01-01 69.7095 2015-01-01 90.3793 2016-01-01 85.9055