Year	Percent
1991-01-01	79.5080032348633
1992-01-01	79.7639999389648
1993-01-01	80.0729980468750
1994-01-01	80.0979995727539
1995-01-01	79.9739990234375
1996-01-01	79.7239990234375
1997-01-01	77.9520034790039
1998-01-01	75.9400024414063
1999-01-01	76.9520034790039
2000-01-01	76.6600036621094
2001-01-01	81.7460021972656
2002-01-01	80.9960021972656
2003-01-01	80.1129989624023
2004-01-01	78.6849975585938
2005-01-01	79.8880004882813
2006-01-01	81.0960006713867
2007-01-01	82.5999984741211
2008-01-01	83.7789993286133
2009-01-01	84.6149978637695
2010-01-01	85.0940017700195
2011-01-01	85.0189971923828
2012-01-01	84.8499984741211
2013-01-01	84.5360031127930
2014-01-01	84.4779968261719
2015-01-01	84.3430023193359
2016-01-01	84.2129974365234
2017-01-01	84.4530029296875