Year	Percent
1991-01-01	9.621000289916990
1992-01-01	9.508999824523930
1993-01-01	9.550000190734860
1994-01-01	9.569000244140630
1995-01-01	9.413999557495120
1996-01-01	8.482999801635740
1997-01-01	7.343999862670900
1998-01-01	6.448999881744380
1999-01-01	5.249000072479250
2000-01-01	4.163000106811520
2001-01-01	3.196000099182130
2002-01-01	3.798000097274780
2003-01-01	4.443999767303470
2004-01-01	4.960999965667720
2005-01-01	5.717999935150150
2006-01-01	5.372000217437740
2007-01-01	4.393000125885010
2008-01-01	3.502000093460080
2009-01-01	2.415999889373780
2010-01-01	1.491000056266780
2011-01-01	0.481999993324280
2012-01-01	0.572000026702881
2013-01-01	0.515999972820282
2014-01-01	0.540000021457672
2015-01-01	0.501999974250793
2016-01-01	0.515999972820282
2017-01-01	0.528999984264374