Year	Percent
1999-01-01	69.700
2000-01-01	67.775
2001-01-01	65.725
2002-01-01	66.400
2003-01-01	63.500
2004-01-01	66.000
2005-01-01	66.225
2006-01-01	69.325
2007-01-01	69.150
2008-01-01	71.450
2009-01-01	70.050
2010-01-01	67.425
2011-01-01	67.100
2012-01-01	64.025
2013-01-01	62.450
2014-01-01	62.000
2015-01-01	62.500
2016-01-01	67.375
2017-01-01	64.100