Year	Percent
1999-01-01	26.975
2000-01-01	27.300
2001-01-01	27.725
2002-01-01	27.775
2003-01-01	27.325
2004-01-01	29.750
2005-01-01	29.325
2006-01-01	28.850
2007-01-01	28.025
2008-01-01	28.025
2009-01-01	28.175
2010-01-01	28.250
2011-01-01	28.375
2012-01-01	28.300
2013-01-01	28.250
2014-01-01	28.650
2015-01-01	28.250
2016-01-01	27.600
2017-01-01	27.250