Year	Percent
1999-01-01	61.200
2000-01-01	59.125
2001-01-01	58.100
2002-01-01	56.975
2003-01-01	56.000
2004-01-01	55.550
2005-01-01	54.025
2006-01-01	53.175
2007-01-01	52.675
2008-01-01	50.900
2009-01-01	49.975
2010-01-01	49.250
2011-01-01	47.600
2012-01-01	46.500
2013-01-01	45.950
2014-01-01	44.600
2015-01-01	42.375
2016-01-01	40.800
2017-01-01	40.375