Year	Percent
2001-01-01	4.52
2002-01-01	4.52
2003-01-01	4.52
2004-01-01	4.52
2005-01-01	6.56
2006-01-01	7.08
2007-01-01	7.67
2008-01-01	7.39
2009-01-01	7.57
2010-01-01	8.02
2011-01-01	8.45
2012-01-01	8.51
2013-01-01	8.72
2014-01-01	8.97
2015-01-01	9.06