Year	Percent
1964-01-01	0.499797999999999960
1965-01-01	1.699300000000000000
1966-01-01	2.602360000000000000
1967-01-01	2.693780000000000000
1968-01-01	2.193670000000000000
1969-01-01	1.612339999999999900
1970-01-01	1.897150000000000000
1971-01-01	1.766209999999999800
1972-01-01	1.157700000000000000
1973-01-01	1.471730000000000000
1974-01-01	1.776840000000000200
1975-01-01	2.070410000000000000
1976-01-01	2.814850000000000000
1977-01-01	2.374710000000000000
1978-01-01	1.855999999999999900
1979-01-01	2.541470000000000000
1980-01-01	3.078420000000000000
1981-01-01	2.720080000000000000
1982-01-01	2.639430000000000000
1983-01-01	2.631180000000000000
1984-01-01	2.533909999999999700
1985-01-01	2.451710000000000000
1986-01-01	2.125130000000000000
1987-01-01	1.960070000000000000
1988-01-01	1.888620000000000000
1989-01-01	1.772279999999999900
1990-01-01	1.647009999999999900
1991-01-01	1.392630000000000000
1992-01-01	1.103020000000000100
1993-01-01	0.953263999999999900
1994-01-01	0.748634000000000000
1995-01-01	0.509459000000000000
1996-01-01	0.332509000000000000
1997-01-01	0.240838000000000020
1998-01-01	0.209445000000000000
1999-01-01	0.239300000000000000
2000-01-01	0.237355000000000000
2001-01-01	0.023344000000000000
2002-01-01	0.010953000000000001
2003-01-01	0.009556000000000000
2004-01-01	0.011004000000000000
2005-01-01	0.009342000000000000
2006-01-01	0.018077000000000000
2007-01-01	0.034076000000000000
2008-01-01	0.160096000000000020
2009-01-01	0.437735000000000040
2010-01-01	1.039600000000000000
2011-01-01	1.483250000000000000
2012-01-01	1.440050000000000000
2013-01-01	9.954720000000000000
2014-01-01	18.127800000000000000
2015-01-01	15.078200000000000000
2016-01-01	16.413500000000000000