Year	Percent
1991-01-01	8.68700027465820
1992-01-01	8.67599964141846
1993-01-01	8.67500019073486
1994-01-01	8.67000007629395
1995-01-01	8.70600032806396
1996-01-01	8.68200016021729
1997-01-01	8.69699954986572
1998-01-01	8.72299957275391
1999-01-01	8.72900009155273
2000-01-01	8.70199966430664
2001-01-01	8.71399974822998
2002-01-01	8.68500041961670
2003-01-01	10.22399997711180
2004-01-01	11.70600032806400
2005-01-01	13.19299983978270
2006-01-01	14.63899993896480
2007-01-01	14.21199989318850
2008-01-01	13.74499988555910
2009-01-01	13.28800010681150
2010-01-01	12.88599967956540
2011-01-01	12.53100013732910
2012-01-01	10.80300045013430
2013-01-01	9.02200031280518
2014-01-01	7.25699996948242
2015-01-01	5.30200004577637
2016-01-01	5.38999986648560
2017-01-01	5.47200012207031