Year Percent 1997-01-01 0.74725900000000000 1998-01-01 0.42083400000000004 1999-01-01 0.42083400000000004 2000-01-01 0.42083400000000004 2001-01-01 0.87288400000000000 2002-01-01 0.87824599999999990 2003-01-01 0.85094699999999990 2004-01-01 0.38375600000000000 2005-01-01 0.38283800000000000 2006-01-01 0.32465900000000003 2007-01-01 0.32618600000000003 2008-01-01 0.28659100000000000 2009-01-01 0.39102900000000000 2010-01-01 0.44023599999999996 2011-01-01 0.33288800000000000 2012-01-01 0.29734499999999997 2013-01-01 0.31809299999999996 2014-01-01 0.34019299999999997 2015-01-01 0.44428700000000000 2016-01-01 0.47286100000000000