Year	Percent
1986-01-01	4.6000000000000000
1987-01-01	3.7166699999999997
1988-01-01	3.5416700000000000
1989-01-01	3.7750000000000000
1990-01-01	3.9000000000000000
1991-01-01	4.1250000000000000
1992-01-01	4.7083300000000000
1993-01-01	5.6250000000000000
1994-01-01	6.6083300000000005
1995-01-01	6.2333300000000005
1996-01-01	6.1083300000000005
1997-01-01	5.8916699999999995
1998-01-01	6.1416699999999995
1999-01-01	6.9750000000000000
2000-01-01	5.8666700000000000
2001-01-01	6.2583300000000000
2002-01-01	7.5250000000000000
2003-01-01	6.1666700000000000
2004-01-01	7.3250000000000000
2005-01-01	7.5916700000000000
2006-01-01	7.4333300000000010
2007-01-01	6.9750000000000000
2008-01-01	7.6166700000000000
2009-01-01	7.4166700000000000
2010-01-01	8.0750000000000000
2011-01-01	7.9833300000000005
2012-01-01	7.6416699999999995
2013-01-01	7.0916700000000000
2014-01-01	6.0583300000000010
2015-01-01	6.3000000000000000
2016-01-01	6.1083300000000005