Year	Percent
1997-01-01	100.00000000000000
1998-01-01	97.53230000000000
1999-01-01	95.12210000000000
2000-01-01	91.78270000000000
2001-01-01	97.33020000000000
2002-01-01	96.36900000000000
2003-01-01	86.50140000000000
2004-01-01	82.87570000000000
2005-01-01	77.14880000000000
2006-01-01	81.43020000000000
2007-01-01	87.92600000000000
2008-01-01	87.99020000000000
2009-01-01	89.15799999999999
2010-01-01	85.11170000000000
2011-01-01	82.93720000000000
2012-01-01	81.67280000000000
2013-01-01	83.72530000000000
2014-01-01	87.54580000000000
2015-01-01	83.20210000000000
2016-01-01	92.32840000000000