Year	Percent
2001-01-01	4.17
2002-01-01	4.24
2003-01-01	4.55
2004-01-01	4.39
2005-01-01	4.54
2006-01-01	4.65
2007-01-01	4.87
2008-01-01	4.79
2009-01-01	5.32
2010-01-01	5.31
2011-01-01	5.44
2012-01-01	5.63
2013-01-01	5.79
2014-01-01	6.34
2015-01-01	6.46
2016-01-01	6.77