Year	Percent
2000-01-01	40.700
2001-01-01	39.750
2002-01-01	38.500
2003-01-01	38.150
2004-01-01	38.225
2005-01-01	38.550
2006-01-01	39.650
2007-01-01	41.475
2008-01-01	42.900
2009-01-01	43.175
2010-01-01	42.825
2011-01-01	42.800
2012-01-01	42.900
2013-01-01	42.800
2014-01-01	43.825
2015-01-01	44.700
2016-01-01	45.325
2017-01-01	46.075