Year	Percent
2005-01-01	55.800
2006-01-01	55.775
2007-01-01	55.825
2008-01-01	55.725
2009-01-01	56.400
2010-01-01	57.075
2011-01-01	57.425
2012-01-01	57.575
2013-01-01	57.875
2014-01-01	58.325
2015-01-01	58.425
2016-01-01	58.400
2017-01-01	58.350