Year Percent 1996-01-01 76.1639 1997-01-01 64.7036 1998-01-01 85.3857 1999-01-01 95.9883 2000-01-01 92.8943 2001-01-01 95.9464 2002-01-01 98.3002 2003-01-01 100.0000 2004-01-01 97.8846 2005-01-01 94.7694 2006-01-01 85.1684 2007-01-01 84.9463 2008-01-01 94.0925 2009-01-01 88.7845 2010-01-01 89.6809 2011-01-01 89.9116 2012-01-01 89.9136 2013-01-01 86.6517 2014-01-01 87.5371 2015-01-01 87.2397 2016-01-01 86.1468