Year	Percent
1999-01-01	49.975
2000-01-01	48.800
2001-01-01	48.850
2002-01-01	48.850
2003-01-01	49.675
2004-01-01	49.150
2005-01-01	49.800
2006-01-01	51.250
2007-01-01	52.275
2008-01-01	53.675
2009-01-01	51.775
2010-01-01	50.500
2011-01-01	50.750
2012-01-01	50.925
2013-01-01	50.850
2014-01-01	51.500
2015-01-01	52.775
2016-01-01	54.250
2017-01-01	55.075