Year	Percent
2002-01-01	21.60
2003-01-01	24.10
2004-01-01	22.20
2005-01-01	22.20
2006-01-01	22.20
2007-01-01	8.40
2008-01-01	11.30
2009-01-01	15.70
2010-01-01	16.90
2011-01-01	20.00
2012-01-01	18.60
2013-01-01	21.37
2014-01-01	21.54
2015-01-01	21.58