Year	Percent
1999-01-01	74.975
2000-01-01	73.450
2001-01-01	70.275
2002-01-01	70.700
2003-01-01	67.725
2004-01-01	69.750
2005-01-01	70.025
2006-01-01	70.525
2007-01-01	72.025
2008-01-01	72.800
2009-01-01	71.775
2010-01-01	67.550
2011-01-01	67.125
2012-01-01	64.100
2013-01-01	61.075
2014-01-01	61.050
2015-01-01	61.725
2016-01-01	65.000
2017-01-01	62.475