Year	Percent
1998-01-01	59.625
1999-01-01	59.050
2000-01-01	59.475
2001-01-01	59.875
2002-01-01	58.700
2003-01-01	56.875
2004-01-01	58.300
2005-01-01	56.400
2006-01-01	55.850
2007-01-01	55.850
2008-01-01	55.575
2009-01-01	55.625
2010-01-01	54.800
2011-01-01	56.900
2012-01-01	57.875
2013-01-01	57.550
2014-01-01	58.900
2015-01-01	58.400
2016-01-01	55.125
2017-01-01	53.275