Year	Percent
1970-01-01	0.29007300000000000
1971-01-01	0.28224099999999996
1972-01-01	1.67930000000000000
1973-01-01	3.21034000000000000
1974-01-01	3.77415999999999970
1975-01-01	3.95344000000000000
1976-01-01	3.85780999999999970
1977-01-01	4.55347000000000000
1978-01-01	5.55403000000000000
1979-01-01	5.48929000000000040
1980-01-01	6.92953000000000100
1981-01-01	12.29010000000000000
1982-01-01	10.34160000000000000
1983-01-01	4.03955000000000000
1984-01-01	3.28389000000000000
1985-01-01	2.93817000000000000
1986-01-01	1.85025000000000000
1987-01-01	0.74815900000000000
1988-01-01	0.78856800000000000
1989-01-01	0.80215100000000010
1990-01-01	0.84881500000000000
1991-01-01	0.73439800000000000
1992-01-01	0.40482199999999996
1993-01-01	0.33849300000000000
1994-01-01	0.24545400000000000
1995-01-01	0.01187400000000000
1996-01-01	0.11559600000000000
1997-01-01	0.22481800000000000
1998-01-01	0.22176500000000002
1999-01-01	0.22369200000000000
2000-01-01	0.21848000000000000
2001-01-01	0.21885900000000003
2002-01-01	0.23360600000000000
2003-01-01	0.22405000000000000
2004-01-01	0.22882000000000000
2005-01-01	0.14132999999999998
2006-01-01	0.09516500000000000
2007-01-01	0.15956700000000001
2008-01-01	0.19073099999999998
2009-01-01	0.19156400000000000
2010-01-01	0.19860000000000000
2011-01-01	0.18001800000000000
2012-01-01	0.16736199999999998
2013-01-01	0.25276100000000000
2014-01-01	1.31645000000000000
2015-01-01	2.14913000000000000
2016-01-01	1.74210000000000000