Year	Percent
2000-01-01	58.700
2001-01-01	58.925
2002-01-01	57.775
2003-01-01	57.125
2004-01-01	57.025
2005-01-01	55.850
2006-01-01	54.725
2007-01-01	53.975
2008-01-01	53.350
2009-01-01	47.900
2010-01-01	47.550
2011-01-01	46.300
2012-01-01	46.350
2013-01-01	46.375
2014-01-01	48.225
2015-01-01	50.275
2016-01-01	50.550
2017-01-01	50.450