Year	Percent
2001-01-01	17.41
2002-01-01	15.28
2003-01-01	13.29
2004-01-01	13.09
2005-01-01	12.71
2006-01-01	13.07
2007-01-01	12.38
2008-01-01	10.25
2009-01-01	12.40
2010-01-01	14.17
2011-01-01	14.59
2012-01-01	17.11
2013-01-01	18.80
2014-01-01	21.49
2015-01-01	23.32
2016-01-01	24.83