Year	Percent
1960-01-01	2.5326800000000000
1961-01-01	2.3996299999999997
1962-01-01	2.3858300000000000
1963-01-01	3.6078900000000003
1964-01-01	5.9366100000000000
1965-01-01	7.1946000000000000
1966-01-01	7.3667399999999990
1967-01-01	8.0632500000000000
1968-01-01	9.2898500000000000
1969-01-01	9.8087300000000000
1970-01-01	8.7575500000000000
1971-01-01	8.1598200000000000
1972-01-01	8.1324899999999990
1973-01-01	8.4304899999999990
1974-01-01	7.1937200000000000
1975-01-01	7.5187800000000005
1976-01-01	8.2301899999999990
1977-01-01	8.9600300000000000
1978-01-01	10.1953000000000000
1979-01-01	10.8276000000000000
1980-01-01	10.7444000000000000
1981-01-01	12.3823000000000000
1982-01-01	12.6694000000000000
1983-01-01	13.9172000000000000
1984-01-01	14.6978000000000000
1985-01-01	13.8528000000000000
1986-01-01	12.7053000000000000
1987-01-01	12.3835000000000000
1988-01-01	10.5741000000000000
1989-01-01	9.9993100000000010
1990-01-01	8.7953400000000000
1991-01-01	8.2116300000000000
1992-01-01	7.4313300000000000
1993-01-01	6.0566600000000000
1994-01-01	5.2940300000000000
1995-01-01	6.7547100000000000
1996-01-01	7.5046200000000000
1997-01-01	7.4999699999999990
1998-01-01	6.9423200000000000
1999-01-01	5.9514400000000000
2000-01-01	5.5260700000000000
2001-01-01	4.5040400000000000
2002-01-01	3.5157100000000000
2003-01-01	3.4793500000000000
2004-01-01	3.4872000000000000
2005-01-01	2.9617600000000000
2006-01-01	2.4130400000000000
2007-01-01	2.1593400000000003
2008-01-01	1.8344400000000000
2009-01-01	1.5475800000000000
2010-01-01	1.1899400000000000
2011-01-01	0.9200910000000000
2012-01-01	0.7251110000000000
2013-01-01	0.6672540000000000
2014-01-01	0.6237280000000000
2015-01-01	0.5552440000000000
2016-01-01	0.5554279999999999