Year	Percent
1999-01-01	2.9683800000000000
2000-01-01	3.1236200000000003
2001-01-01	2.2586800000000000
2002-01-01	2.2141300000000000
2003-01-01	3.0825500000000000
2004-01-01	5.4093100000000000
2005-01-01	6.1558100000000000
2006-01-01	6.6283800000000000
2007-01-01	7.6801400000000000
2008-01-01	3.0227700000000000
2009-01-01	5.2209699999999994
2010-01-01	6.9502500000000000
2011-01-01	4.7887800000000000
2012-01-01	7.4003100000000000
2013-01-01	8.0516600000000000
2014-01-01	7.0424399999999990
2015-01-01	7.7800400000000000
2016-01-01	7.4356500000000000