Year Percent 1999-01-01 98.0913 2000-01-01 98.1973 2001-01-01 98.3547 2002-01-01 98.4307 2003-01-01 99.2253 2004-01-01 99.9952 2005-01-01 99.9948 2006-01-01 99.9929 2007-01-01 99.9919 2008-01-01 99.9921 2009-01-01 99.9898 2010-01-01 99.9883 2011-01-01 97.9263 2012-01-01 97.9487 2013-01-01 99.9875 2014-01-01 99.9851 2015-01-01 99.9841 2016-01-01 99.9851