Year	Percent
1999-01-01	11.400
2000-01-01	13.500
2001-01-01	15.075
2002-01-01	17.950
2003-01-01	22.350
2004-01-01	25.775
2005-01-01	27.675
2006-01-01	27.675
2007-01-01	26.875
2008-01-01	26.625
2009-01-01	28.075
2010-01-01	31.675
2011-01-01	34.750
2012-01-01	34.500
2013-01-01	34.725
2014-01-01	37.375
2015-01-01	39.900
2016-01-01	43.475
2017-01-01	44.300