Year	Percent
2003-01-01	40.875
2004-01-01	41.650
2005-01-01	41.525
2006-01-01	40.550
2007-01-01	40.500
2008-01-01	40.575
2009-01-01	41.500
2010-01-01	42.250
2011-01-01	44.050
2012-01-01	47.550
2013-01-01	48.400
2014-01-01	48.850
2015-01-01	50.700
2016-01-01	51.575
2017-01-01	52.750