Year Percent 1998-01-01 88.5498 1999-01-01 84.5839 2000-01-01 62.3000 2001-01-01 62.5000 2002-01-01 62.6430 2003-01-01 63.0383 2004-01-01 66.8040 2005-01-01 80.9770 2006-01-01 73.4889 2007-01-01 78.5893 2008-01-01 76.2307 2009-01-01 80.7508 2010-01-01 79.0615 2011-01-01 78.6400 2012-01-01 79.6057 2013-01-01 79.6057 2014-01-01 82.6038 2015-01-01 86.8156 2016-01-01 87.0010