Year	Percent
1998-01-01	18.6000000000000000
1999-01-01	16.6000000000000000
2000-01-01	15.4000000000000000
2001-01-01	17.8000000000000000
2002-01-01	15.9000000000000000
2003-01-01	13.9000000000000000
2004-01-01	11.7000000000000000
2005-01-01	9.4000000000000000
2006-01-01	8.5000000000000000
2007-01-01	6.5000000000000000
2008-01-01	4.8000000000000000
2009-01-01	3.6000000000000000
2010-01-01	3.3540300000000003
2011-01-01	2.6813900000000000
2012-01-01	2.0158400000000003
2013-01-01	1.8491500000000000
2014-01-01	1.6457900000000000
2015-01-01	1.6013899999999999
2016-01-01	1.6119000000000000