Year	Percent
2000-01-01	5.46
2001-01-01	6.82
2002-01-01	8.23
2003-01-01	10.64
2004-01-01	11.27
2005-01-01	13.04
2006-01-01	15.83
2007-01-01	18.89
2008-01-01	13.88
2009-01-01	18.82
2010-01-01	20.66
2011-01-01	17.62
2012-01-01	19.43
2013-01-01	19.09
2014-01-01	19.87
2015-01-01	20.64
2016-01-01	20.70