Year	Percent
1999-01-01	61.525
2000-01-01	62.025
2001-01-01	63.250
2002-01-01	62.450
2003-01-01	61.700
2004-01-01	64.400
2005-01-01	64.725
2006-01-01	65.425
2007-01-01	66.700
2008-01-01	66.250
2009-01-01	64.825
2010-01-01	63.950
2011-01-01	62.050
2012-01-01	61.450
2013-01-01	60.950
2014-01-01	61.550
2015-01-01	62.150
2016-01-01	61.250
2017-01-01	64.275