Year	Percent
1991-01-01	3.1575599999999997
1992-01-01	3.4484500000000000
1993-01-01	4.3709600000000000
1994-01-01	5.0544699999999990
1995-01-01	5.3458000000000000
1996-01-01	5.7872400000000000
1997-01-01	6.0947800000000000
1998-01-01	4.8844900000000000
1999-01-01	5.4686000000000000
2000-01-01	6.2664200000000000
2001-01-01	5.6530200000000000
2002-01-01	5.5308300000000000
2003-01-01	5.7907699999999990
2004-01-01	6.3761100000000000
2005-01-01	7.0348000000000000
2006-01-01	7.7909200000000000
2007-01-01	7.2637600000000000
2008-01-01	6.3362800000000000
2009-01-01	7.3173300000000000
2010-01-01	7.6637400000000000
2011-01-01	6.4831100000000000
2012-01-01	5.8284800000000000
2013-01-01	6.0415600000000000
2014-01-01	6.2848000000000000
2015-01-01	5.8592500000000000
2016-01-01	5.4780100000000000