Year	Percent
1983-01-01	12.518400000000000
1984-01-01	12.325800000000000
1985-01-01	16.267100000000000
1986-01-01	16.700000000000000
1987-01-01	16.505400000000000
1988-01-01	13.257300000000000
1989-01-01	12.069600000000000
1990-01-01	9.722140000000000
1991-01-01	8.956220000000000
1992-01-01	7.368080000000000
1993-01-01	7.300590000000000
1994-01-01	9.031170000000000
1995-01-01	8.731110000000001
1996-01-01	9.430019999999999
1997-01-01	14.170900000000000
1998-01-01	13.924700000000000
1999-01-01	15.664700000000000
2000-01-01	14.962600000000000
2001-01-01	13.079000000000000
2002-01-01	16.256400000000000
2003-01-01	21.862000000000000
2004-01-01	22.534000000000002
2005-01-01	18.799500000000000
2006-01-01	20.336500000000000
2007-01-01	18.566000000000000
2008-01-01	17.547600000000000
2009-01-01	18.675400000000000
2010-01-01	17.409300000000000
2011-01-01	17.611400000000000
2012-01-01	18.532800000000000
2013-01-01	19.371000000000000
2014-01-01	17.222300000000000
2015-01-01	17.686100000000000
2016-01-01	17.503400000000000