Year Percent 1996-01-01 82.2223 1997-01-01 83.6266 1998-01-01 84.9357 1999-01-01 90.1288 2000-01-01 82.0203 2001-01-01 86.4639 2002-01-01 90.9505 2003-01-01 98.7297 2004-01-01 93.0657 2005-01-01 78.3596 2006-01-01 77.2822 2007-01-01 79.2644 2008-01-01 77.7781 2009-01-01 77.1065 2010-01-01 72.2041 2011-01-01 69.2220 2012-01-01 69.8470 2013-01-01 76.9011 2014-01-01 77.0938 2015-01-01 76.3254 2016-01-01 80.8600