Year	Percent
1979-01-01	3.6716699999999998
1980-01-01	4.1174400000000000
1981-01-01	4.7221400000000004
1982-01-01	6.2502400000000000
1983-01-01	5.9523000000000000
1984-01-01	5.3190599999999995
1985-01-01	12.6240000000000000
1986-01-01	12.8190000000000000
1987-01-01	15.1773000000000000
1988-01-01	9.4381200000000000
1989-01-01	10.1904000000000000
1990-01-01	12.9200000000000000
1991-01-01	12.7496000000000000
1992-01-01	12.6180000000000000
1993-01-01	13.0047000000000000
1994-01-01	12.5831000000000000
1995-01-01	12.5831000000000000
1996-01-01	12.5831000000000000
1997-01-01	12.5831000000000000
1998-01-01	12.5831000000000000
1999-01-01	12.5831000000000000
2000-01-01	12.5831000000000000
2001-01-01	12.5831000000000000
2002-01-01	12.5831000000000000
2003-01-01	12.5831000000000000
2004-01-01	12.5831000000000000
2005-01-01	0.0000000000000000
2006-01-01	11.9675000000000000
2007-01-01	10.6617000000000000
2008-01-01	10.3306000000000000
2009-01-01	10.7673000000000000
2010-01-01	10.2103000000000000
2011-01-01	9.6141000000000000
2012-01-01	9.3820300000000000
2013-01-01	9.1892000000000000
2014-01-01	9.3796900000000000
2015-01-01	9.5161300000000000
2016-01-01	9.6254700000000000
2017-01-01	9.3559600000000010