Year	Percent
2000-01-01	88.0202311069844
2001-01-01	87.9788776537424
2002-01-01	88.7338479431523
2003-01-01	88.8558147721009
2004-01-01	88.4457903791529
2005-01-01	87.8966868573164
2006-01-01	87.5387530420799
2007-01-01	87.2680462362844
2008-01-01	87.2693712185072
2009-01-01	86.2530399543969
2010-01-01	86.7764132724970
2011-01-01	87.4430322012821
2012-01-01	87.8249371933974
2013-01-01	87.8885532653404
2014-01-01	88.3988757031395
2015-01-01	88.1546147506213
2016-01-01	87.9371484298579
2017-01-01	87.6753746434005