Year	Percent
1999-01-01	22.250
2000-01-01	21.350
2001-01-01	22.350
2002-01-01	22.825
2003-01-01	24.650
2004-01-01	26.750
2005-01-01	30.275
2006-01-01	33.050
2007-01-01	35.625
2008-01-01	39.225
2009-01-01	39.500
2010-01-01	40.550
2011-01-01	41.350
2012-01-01	43.050
2013-01-01	44.050
2014-01-01	44.775
2015-01-01	46.975
2016-01-01	49.050
2017-01-01	52.950