Year	Percent
1970-01-01	5.899999998999920
1971-01-01	4.815864023652670
1972-01-01	7.657657657657610
1973-01-01	11.129707112133800
1974-01-01	19.427710843520400
1975-01-01	11.979823455308900
1976-01-01	11.499999999999600
1977-01-01	14.566517189387700
1978-01-01	6.921521299524060
1979-01-01	14.246491763078400
1980-01-01	11.111111111111300
1981-01-01	7.699999999999760
1982-01-01	7.428040854224910
1983-01-01	5.020167098314600
1984-01-01	3.847472738376140
1985-01-01	2.985074627147530
1986-01-01	0.000000000000000
1987-01-01	-0.199999999999877
1988-01-01	6.613226452905760
1989-01-01	25.712719298245400
1990-01-01	16.192137561523300
1991-01-01	8.155495978552130
1992-01-01	3.995835605571910
1993-01-01	3.316666666667030
1994-01-01	3.516696241328870
1995-01-01	2.353124513012730
1996-01-01	6.501218026795870
1997-01-01	3.037884203002500
1998-01-01	3.091666666667010
1999-01-01	0.606256567779459
2000-01-01	0.666880925597929
2001-01-01	1.772204373510170
2002-01-01	1.832993890020500
2003-01-01	1.629999999999970
2004-01-01	3.361868214766030
2005-01-01	3.493685346195310
2006-01-01	6.251724666564410
2007-01-01	4.743565852951540
2008-01-01	13.970704514904700
2009-01-01	-0.739738619906186
2010-01-01	4.839329710461480
2011-01-01	4.169270898439150
2012-01-01	4.515199999999990
2013-01-01	4.824561403508780
2014-01-01	2.898931703505720
2015-01-01	-0.876913360346865
2016-01-01	-0.778579635009077
2017-01-01	3.324457271702370