Year	Percent
1999-01-01	43.125
2000-01-01	43.925
2001-01-01	43.050
2002-01-01	44.175
2003-01-01	44.875
2004-01-01	45.300
2005-01-01	47.925
2006-01-01	48.175
2007-01-01	47.875
2008-01-01	47.725
2009-01-01	45.025
2010-01-01	42.650
2011-01-01	40.925
2012-01-01	39.025
2013-01-01	37.775
2014-01-01	35.725
2015-01-01	34.700
2016-01-01	33.025
2017-01-01	33.350