Year Percent 1996-01-01 65.4154 1997-01-01 69.4661 1998-01-01 63.7928 1999-01-01 68.4338 2000-01-01 66.6943 2001-01-01 66.2323 2002-01-01 67.1982 2003-01-01 60.6487 2004-01-01 61.9429 2005-01-01 71.9259 2006-01-01 77.2337 2007-01-01 77.0439 2008-01-01 63.6802 2009-01-01 75.1573 2010-01-01 78.4830 2011-01-01 72.8345 2012-01-01 71.6114 2013-01-01 65.7043 2014-01-01 63.6207