Year	Percent
1999-01-01	73.225
2000-01-01	73.050
2001-01-01	73.375
2002-01-01	73.100
2003-01-01	73.025
2004-01-01	73.050
2005-01-01	73.000
2006-01-01	73.925
2007-01-01	73.525
2008-01-01	73.975
2009-01-01	70.350
2010-01-01	68.000
2011-01-01	67.950
2012-01-01	67.150
2013-01-01	66.625
2014-01-01	67.175
2015-01-01	67.975
2016-01-01	69.275
2017-01-01	68.175