Year	Percent
1999-01-01	30.750
2000-01-01	34.475
2001-01-01	35.425
2002-01-01	36.875
2003-01-01	38.925
2004-01-01	39.725
2005-01-01	42.325
2006-01-01	42.975
2007-01-01	42.100
2008-01-01	39.775
2009-01-01	41.450
2010-01-01	42.175
2011-01-01	43.675
2012-01-01	45.375
2013-01-01	49.000
2014-01-01	53.175
2015-01-01	57.800
2016-01-01	62.375
2017-01-01	64.500