Year	Percent
1999-01-01	23.300
2000-01-01	20.450
2001-01-01	16.650
2002-01-01	18.500
2003-01-01	19.500
2004-01-01	18.725
2005-01-01	16.725
2006-01-01	15.000
2007-01-01	15.225
2008-01-01	23.625
2009-01-01	39.100
2010-01-01	43.100
2011-01-01	48.175
2012-01-01	54.175
2013-01-01	56.250
2014-01-01	53.425
2015-01-01	48.675
2016-01-01	44.050
2017-01-01	39.600