Year	Percent
1998-01-01	21.800
1999-01-01	23.050
2000-01-01	21.625
2001-01-01	21.625
2002-01-01	19.575
2003-01-01	18.775
2004-01-01	18.950
2005-01-01	18.925
2006-01-01	17.575
2007-01-01	15.500
2008-01-01	16.900
2009-01-01	19.525
2010-01-01	26.875
2011-01-01	38.850
2012-01-01	48.450
2013-01-01	53.775
2014-01-01	47.400
2015-01-01	45.175
2016-01-01	44.350
2017-01-01	39.375