Year	Percent
2005-01-01	80.900
2006-01-01	81.200
2007-01-01	81.600
2008-01-01	82.300
2009-01-01	82.500
2010-01-01	81.275
2011-01-01	82.075
2012-01-01	82.300
2013-01-01	82.400
2014-01-01	82.900
2015-01-01	83.300
2016-01-01	83.875
2017-01-01	83.950