Year	Percent
1983-01-01	0.200
1984-01-01	0.200
1985-01-01	0.200
1986-01-01	0.410
1987-01-01	0.410
1988-01-01	0.410
1989-01-01	0.410
1990-01-01	0.410
1991-01-01	0.410
1992-01-01	0.140
1993-01-01	0.140
1994-01-01	37.410
1995-01-01	38.470
1996-01-01	32.170
1997-01-01	32.440
1998-01-01	51.610
1999-01-01	36.095
2000-01-01	30.355
2001-01-01	27.760
2002-01-01	25.400
2003-01-01	27.530
2004-01-01	19.130
2005-01-01	22.210
2006-01-01	17.165
2007-01-01	14.400
2008-01-01	10.735
2009-01-01	12.525
2010-01-01	11.650
2011-01-01	9.360
2012-01-01	10.460
2013-01-01	13.330
2014-01-01	14.360
2015-01-01	19.775