Year	Percent
1999-01-01	62.200
2000-01-01	62.850
2001-01-01	63.800
2002-01-01	63.450
2003-01-01	62.575
2004-01-01	65.275
2005-01-01	65.950
2006-01-01	66.550
2007-01-01	67.750
2008-01-01	68.575
2009-01-01	67.525
2010-01-01	66.200
2011-01-01	64.400
2012-01-01	64.075
2013-01-01	63.275
2014-01-01	63.900
2015-01-01	65.225
2016-01-01	65.850
2017-01-01	69.275