Year	Percent
1998-01-01	11.3976
1999-01-01	10.6414
2000-01-01	10.0708
2001-01-01	12.1566
2002-01-01	12.2030
2003-01-01	10.5009
2004-01-01	11.8053
2005-01-01	14.5347
2006-01-01	14.2601
2007-01-01	19.5015
2008-01-01	18.4190
2009-01-01	12.7407
2010-01-01	12.2095
2011-01-01	14.0694
2012-01-01	14.0525
2013-01-01	15.8482
2014-01-01	19.4695
2015-01-01	22.5422
2016-01-01	21.5087