Year Percent 1999-01-01 100.0000 2000-01-01 100.0000 2001-01-01 99.3979 2002-01-01 99.8137 2003-01-01 94.4475 2004-01-01 91.4774 2005-01-01 88.3483 2006-01-01 87.3733 2007-01-01 83.8875 2008-01-01 90.3305 2009-01-01 82.9844 2010-01-01 80.1777 2011-01-01 74.4277 2012-01-01 78.5094 2013-01-01 79.3959 2014-01-01 82.0791 2015-01-01 69.1773 2016-01-01 70.3079