Year	Percent
1991-01-01	16.4930000305176
1992-01-01	17.2590007781982
1993-01-01	16.5100002288818
1994-01-01	15.3369998931885
1995-01-01	16.4650001525879
1996-01-01	11.6499996185303
1997-01-01	11.7580003738403
1998-01-01	11.3839998245239
1999-01-01	10.7430000305176
2000-01-01	11.2390003204346
2001-01-01	10.8620004653931
2002-01-01	11.1450004577637
2003-01-01	11.0830001831055
2004-01-01	11.0570001602173
2005-01-01	10.8620004653931
2006-01-01	11.3549995422363
2007-01-01	11.3719997406006
2008-01-01	10.9259996414185
2009-01-01	11.3409996032715
2010-01-01	11.2950000762939
2011-01-01	11.1599998474121
2012-01-01	11.1079998016357
2013-01-01	11.1339998245239
2014-01-01	11.1379995346069
2015-01-01	11.3640003204346
2016-01-01	11.7299995422363
2017-01-01	11.6669998168945