Year	Percent
1996-12-31	6.22
1997-12-31	7.305
1998-12-31	5.685
1999-12-31	5.535
2000-12-31	5.665
2001-12-31	3.88
2002-12-31	3.855
2003-12-31	3.855
2004-12-31	4.725
2005-12-31	4.445
2006-12-31	5.15
2007-12-31	5.395
2008-12-31	1.355
2009-12-31	0.485
2010-12-31	0.575
2011-12-31	0.445
2012-12-31	0.445
2013-12-31	0.43
2014-12-31	0.455
2015-12-31	0.61
2016-12-31	0.315
2017-12-31	0.485