Year	Percent
2001-01-01	64.025
2002-01-01	65.550
2003-01-01	66.300
2004-01-01	66.975
2005-01-01	66.650
2006-01-01	66.975
2007-01-01	66.950
2008-01-01	66.675
2009-01-01	66.750
2010-01-01	66.850
2011-01-01	68.900
2012-01-01	69.625
2013-01-01	70.250
2014-01-01	71.500
2015-01-01	72.075
2016-01-01	73.500
2017-01-01	74.425