Year	Percent
1986-01-01	67.2124024498202
1987-01-01	68.1407014589435
1988-01-01	67.4097596485580
1989-01-01	69.4944677453064
1990-01-01	69.3098297507352
1991-01-01	68.7074245614322
1992-01-01	67.4359331401293
1993-01-01	65.1748410709002
1994-01-01	63.4298485720047
1995-01-01	61.0856039828073
1996-01-01	57.1850367032250
1997-01-01	55.6379830204933
1998-01-01	53.8543224734444
1999-01-01	51.8508914028207
2000-01-01	52.2414538044579
2001-01-01	48.2989038542568
2002-01-01	46.0591726816795
2003-01-01	42.2818104036509
2004-01-01	40.3113179129514
2005-01-01	37.6221325432814
2006-01-01	37.8460380516162
2007-01-01	35.9041577433308
2008-01-01	35.2185918165334
2009-01-01	33.6476652257546
2010-01-01	30.9122885592529
2011-01-01	30.4344642524091
2012-01-01	29.1177982335064
2013-01-01	27.7212684773767
2014-01-01	26.0355330867263
2015-01-01	27.2706076114318
2016-01-01	26.8157443397637
2017-01-01	25.4809211837381