Year	Percent
1999-01-01	13.875
2000-01-01	12.325
2001-01-01	9.250
2002-01-01	10.200
2003-01-01	10.275
2004-01-01	9.800
2005-01-01	7.975
2006-01-01	7.475
2007-01-01	7.200
2008-01-01	10.050
2009-01-01	16.350
2010-01-01	18.375
2011-01-01	19.875
2012-01-01	23.250
2013-01-01	24.475
2014-01-01	22.800
2015-01-01	20.550
2016-01-01	18.225
2017-01-01	15.900