Year	Percent
2006-01-01	68.850
2007-01-01	68.800
2008-01-01	69.250
2009-01-01	69.425
2010-01-01	69.900
2011-01-01	70.950
2012-01-01	70.325
2013-01-01	70.875
2014-01-01	71.225
2015-01-01	71.575
2016-01-01	71.950
2017-01-01	72.425