Year	Percent
1981-01-01	2.7708300000000000
1982-01-01	3.6666700000000000
1983-01-01	3.1250000000000000
1984-01-01	4.0000000000000000
1985-01-01	4.1041700000000000
1986-01-01	4.6250000000000000
1987-01-01	6.6666700000000000
1988-01-01	7.7666699999999995
1989-01-01	7.5416700000000000
1990-01-01	7.5000000000000000
1991-01-01	7.4583300000000000
1992-01-01	4.6458300000000000
1993-01-01	6.2500000000000000
1994-01-01	5.5000000000000000
1995-01-01	7.9657000000000000
1996-01-01	9.6664800000000000
1997-01-01	13.1791000000000000
1998-01-01	11.6658000000000000
1999-01-01	10.9125000000000000
2000-01-01	11.5688000000000000
2001-01-01	13.4220000000000000
2002-01-01	13.7400000000000000
2003-01-01	13.6681000000000000
2004-01-01	13.1934000000000000
2005-01-01	13.3612000000000000
2006-01-01	13.2324000000000000
2007-01-01	13.4430000000000000
2008-01-01	13.4858000000000000
2009-01-01	11.1167000000000000
2010-01-01	10.8200000000000000
2011-01-01	10.1700000000000000
2012-01-01	10.5200000000000000
2013-01-01	12.1500000000000000
2014-01-01	10.7100000000000000
2015-01-01	9.8800000000000000
2016-01-01	10.3691000000000000