Year	Percent
2006-01-01	28.5
2007-01-01	31
2008-01-01	32.6
2009-01-01	33.5
2010-01-01	31
2011-01-01	30.3
2012-01-01	28.3
2013-01-01	25
2014-01-01	21.8
2015-01-01	22.4