Year	Percent
1978-01-01	11.0000
1979-01-01	15.5800
1980-01-01	13.8300
1981-01-01	13.5500
1982-01-01	10.7100
1983-01-01	8.9900
1984-01-01	9.1900
1985-01-01	11.5000
1986-01-01	10.8300
1987-01-01	8.5100
1988-01-01	12.5700
1989-01-01	14.9800
1990-01-01	14.3500
1991-01-01	10.7200
1992-01-01	6.8200
1993-01-01	5.8800
1994-01-01	5.4400
1995-01-01	6.6900
1996-01-01	5.8300
1997-01-01	7.1379
1998-01-01	6.3750
1999-01-01	4.7814
2000-01-01	5.7383
2001-01-01	4.5841
2002-01-01	4.3953
2003-01-01	3.7778
2004-01-01	4.7618
2005-01-01	4.6381
2006-01-01	5.0844
2007-01-01	5.5964
2008-01-01	1.6525
2009-01-01	0.4492
2010-01-01	0.5173
2011-01-01	0.5201
2012-01-01	0.4309
2013-01-01	0.4215
2014-01-01	0.4280
2015-01-01	0.4575
2016-01-01	0.2125
2017-01-01	0.4619