Year	Percent
1998-01-01	57.525
1999-01-01	50.925
2000-01-01	49.000
2001-01-01	49.150
2002-01-01	49.125
2003-01-01	50.025
2004-01-01	51.100
2005-01-01	49.575
2006-01-01	48.975
2007-01-01	46.425
2008-01-01	46.475
2009-01-01	48.825
2010-01-01	50.675
2011-01-01	49.500
2012-01-01	47.975
2013-01-01	47.125
2014-01-01	47.400
2015-01-01	46.725
2016-01-01	46.875
2017-01-01	45.825