Year	Percent
2000-01-01	28.325
2001-01-01	28.275
2002-01-01	28.775
2003-01-01	28.850
2004-01-01	28.325
2005-01-01	27.675
2006-01-01	26.600
2007-01-01	23.625
2008-01-01	24.775
2009-01-01	27.725
2010-01-01	29.825
2011-01-01	30.800
2012-01-01	31.250
2013-01-01	31.100
2014-01-01	31.150
2015-01-01	30.900
2016-01-01	30.950
2017-01-01	31.450