Year	Percent
1998-01-01	7.100000000000000
1999-01-01	8.100000000000000
2000-01-01	8.100000000000000
2001-01-01	8.100000000000000
2002-01-01	8.100000000000000
2003-01-01	8.100000000000000
2004-01-01	8.100000000000000
2005-01-01	8.100000000000000
2006-01-01	7.300000000000000
2007-01-01	6.000000000000000
2008-01-01	6.000000000000000
2009-01-01	7.700000000000000
2010-01-01	7.338670000000000
2011-01-01	7.250020000000000
2012-01-01	8.465720000000000
2013-01-01	8.773610000000001
2014-01-01	9.330670000000000
2015-01-01	10.520000000000000
2016-01-01	10.621200000000000