Year	Percent
1999-01-01	16.800
2000-01-01	17.125
2001-01-01	15.875
2002-01-01	18.225
2003-01-01	19.225
2004-01-01	22.125
2005-01-01	23.375
2006-01-01	24.625
2007-01-01	27.450
2008-01-01	27.850
2009-01-01	29.275
2010-01-01	30.875
2011-01-01	32.975
2012-01-01	34.925
2013-01-01	37.850
2014-01-01	38.975
2015-01-01	41.200
2016-01-01	42.750
2017-01-01	45.750
