Year	Percent
2005-01-01	29.5
2006-01-01	29.5
2007-01-01	29.6
2008-01-01	29.6
2009-01-01	30.2
2010-01-01	30.5
2011-01-01	30.7
2012-01-01	30.8
2013-01-01	31.1
2014-01-01	31.2
2015-01-01	31.3
2016-01-01	31.2