Year	Percent
1999-01-01	51.150
2000-01-01	51.525
2001-01-01	51.600
2002-01-01	51.175
2003-01-01	50.025
2004-01-01	52.450
2005-01-01	52.875
2006-01-01	53.250
2007-01-01	53.325
2008-01-01	53.550
2009-01-01	53.625
2010-01-01	53.250
2011-01-01	52.300
2012-01-01	52.250
2013-01-01	51.600
2014-01-01	52.225
2015-01-01	51.900
2016-01-01	52.025
2017-01-01	53.800