Year	Percent
1999-01-01	42.175
2000-01-01	43.600
2001-01-01	42.125
2002-01-01	42.150
2003-01-01	42.925
2004-01-01	38.475
2005-01-01	40.375
2006-01-01	44.075
2007-01-01	47.600
2008-01-01	49.875
2009-01-01	50.550
2010-01-01	51.375
2011-01-01	50.350
2012-01-01	52.250
2013-01-01	55.075
2014-01-01	56.800
2015-01-01	57.375
2016-01-01	61.150
2017-01-01	63.025