Year	Percent
1990-01-01	18.283800000000000
1991-01-01	16.699500000000000
1992-01-01	15.538500000000000
1993-01-01	16.740000000000000
1994-01-01	19.222500000000000
1995-01-01	20.194000000000003
1996-01-01	18.813900000000000
1997-01-01	17.342500000000000
1998-01-01	16.233200000000000
1999-01-01	14.589700000000000
2000-01-01	13.472300000000000
2001-01-01	12.527000000000001
2002-01-01	15.102900000000000
2003-01-01	17.762999999999998
2004-01-01	15.665900000000000
2005-01-01	12.065200000000000
2006-01-01	12.803300000000000
2007-01-01	11.742800000000000
2008-01-01	11.034400000000000
2009-01-01	24.833100000000000
2010-01-01	23.264800000000000
2011-01-01	16.872700000000000
2012-01-01	20.154500000000000
2013-01-01	17.620400000000000
2014-01-01	15.472900000000000
2015-01-01	17.270500000000000
2016-01-01	19.626100000000000