Year	Percent
1999-01-01	76.900
2000-01-01	75.975
2001-01-01	73.525
2002-01-01	74.775
2003-01-01	75.775
2004-01-01	70.075
2005-01-01	67.950
2006-01-01	66.575
2007-01-01	65.450
2008-01-01	65.850
2009-01-01	63.125
2010-01-01	63.525
2011-01-01	66.700
2012-01-01	64.950
2013-01-01	64.000
2014-01-01	61.575
2015-01-01	60.350
2016-01-01	58.800
2017-01-01	54.350