Year	Percent
2000-01-01	51.800
2001-01-01	52.000
2002-01-01	52.275
2003-01-01	52.375
2004-01-01	52.675
2005-01-01	53.025
2006-01-01	53.125
2007-01-01	52.925
2008-01-01	53.125
2009-01-01	52.550
2010-01-01	52.225
2011-01-01	52.075
2012-01-01	52.250
2013-01-01	52.775
2014-01-01	53.725
2015-01-01	54.250
2016-01-01	54.800
2017-01-01	55.300