Year	Percent
1998-01-01	99.65730000000000
1999-01-01	99.39930000000000
2000-01-01	99.39630000000000
2001-01-01	99.48010000000000
2002-01-01	99.52620000000000
2003-01-01	99.51770000000000
2004-01-01	99.62560000000000
2005-01-01	99.65299999999999
2006-01-01	99.54940000000000
2007-01-01	99.63450000000000
2008-01-01	99.61750000000000
2009-01-01	99.60820000000000
2010-01-01	99.81530000000000
2011-01-01	99.91310000000000
2012-01-01	99.93799999999999
2013-01-01	99.95600000000000
2014-01-01	99.99400000000000
2015-01-01	99.98130000000000
2016-01-01	99.91200000000000