Year	Percent
1981-01-01	4.8125000000000000
1982-01-01	5.2500000000000000
1983-01-01	5.3133300000000006
1984-01-01	5.9925000000000000
1985-01-01	7.3741699999999994
1986-01-01	5.9625000000000000
1987-01-01	5.4675000000000000
1988-01-01	6.5733300000000000
1989-01-01	6.7400000000000000
1990-01-01	6.9000000000000000
1991-01-01	8.0300000000000000
1992-01-01	8.4300000000000000
1993-01-01	8.5000000000000000
1994-01-01	9.8800000000000000
1995-01-01	9.8800000000000000
1996-01-01	9.8800000000000000
1997-01-01	8.2000000000000000
1998-01-01	8.7300000000000000
1999-01-01	8.5500000000000000
2000-01-01	8.6200000000000000
2001-01-01	7.7600000000000000
2002-01-01	8.8600000000000000
2003-01-01	6.6900000000000000
2004-01-01	6.0500000000000000
2005-01-01	6.9066700000000000
2006-01-01	6.1287500000000000
2007-01-01	5.0100000000000000
2008-01-01	5.8600000000000000
2009-01-01	8.6800000000000000
2010-01-01	6.8800000000000000
2011-01-01	6.2500000000000000
2012-01-01	6.0000000000000000
2013-01-01	6.0000000000000000
2014-01-01	6.0000000000000000
2015-01-01	7.4300000000000000
2016-01-01	7.5000000000000000