Year	Percent
1998-01-01	3.50000
1999-01-01	3.80000
2000-01-01	4.00000
2001-01-01	4.00000
2002-01-01	4.60000
2003-01-01	5.80000
2004-01-01	5.50000
2005-01-01	4.90000
2006-01-01	5.00000
2007-01-01	5.00000
2008-01-01	4.80000
2009-01-01	5.50000
2010-01-01	5.23442
2011-01-01	4.99763
2012-01-01	6.28378
2013-01-01	6.39190
2014-01-01	6.49563
2015-01-01	7.01052
2016-01-01	7.35565