Year Percent 2007-01-01 100.0000 2008-01-01 96.9582 2009-01-01 96.3547 2010-01-01 96.3547 2011-01-01 94.6475 2012-01-01 93.0288 2013-01-01 87.4368 2014-01-01 89.6324 2015-01-01 78.9944 2016-01-01 81.1281