Year	Percent
1999-01-01	66.975
2000-01-01	65.375
2001-01-01	62.500
2002-01-01	63.300
2003-01-01	65.500
2004-01-01	57.475
2005-01-01	54.600
2006-01-01	54.225
2007-01-01	53.375
2008-01-01	53.625
2009-01-01	51.800
2010-01-01	52.450
2011-01-01	57.325
2012-01-01	56.375
2013-01-01	54.875
2014-01-01	54.300
2015-01-01	53.650
2016-01-01	52.900
2017-01-01	48.225