Year	Percent
1999-01-01	7.68469141397034
2000-01-01	7.05233595902794
2001-01-01	6.78886821079809
2002-01-01	6.80228220688602
2003-01-01	7.09480550837433
2004-01-01	6.81989713913763
2005-01-01	7.03648751659995
2006-01-01	7.18744286022183
2007-01-01	5.83927042870170
2008-01-01	4.83159094513334
2009-01-01	5.80383864304786
2010-01-01	7.01677835040414
2011-01-01	8.17463914128882
2012-01-01	9.36199966964054
2013-01-01	10.90905339423390
2014-01-01	10.55503962972620
2015-01-01	10.03009175917740
2016-01-01	8.59226973620511
2017-01-01	7.48203523485786