Year	Percent
1999-01-01	57.250
2000-01-01	57.450
2001-01-01	58.700
2002-01-01	60.800
2003-01-01	62.800
2004-01-01	64.325
2005-01-01	67.575
2006-01-01	69.150
2007-01-01	69.775
2008-01-01	73.250
2009-01-01	74.600
2010-01-01	74.475
2011-01-01	77.300
2012-01-01	76.400
2013-01-01	76.300
2014-01-01	76.425
2015-01-01	75.125
2016-01-01	75.300
2017-01-01	73.525