Year	Percent
1999-01-01	3.3820900000000003
2000-01-01	3.2518000000000000
2001-01-01	3.1996700000000002
2002-01-01	3.0421600000000000
2003-01-01	2.8971100000000000
2004-01-01	2.2886400000000000
2005-01-01	1.8327300000000000
2006-01-01	1.8484700000000000
2007-01-01	1.8218299999999998
2008-01-01	6.0909600000000000
2009-01-01	6.0401099999999990
2010-01-01	5.0622700000000000
2011-01-01	4.4811600000000000
2012-01-01	4.8529500000000000
2013-01-01	5.2258600000000000
2014-01-01	4.6196000000000000
2015-01-01	4.9485400000000000
2016-01-01	5.8062000000000000