Year	Percent
1960-01-01	3.49731999999999980
1961-01-01	3.49211000000000000
1962-01-01	3.10644000000000000
1963-01-01	2.65623000000000000
1964-01-01	2.60812000000000000
1965-01-01	2.50700999999999970
1966-01-01	2.42552000000000000
1967-01-01	2.07252000000000000
1968-01-01	1.70228000000000000
1969-01-01	3.01102000000000030
1970-01-01	4.53633000000000000
1971-01-01	4.67365000000000000
1972-01-01	4.11711000000000000
1973-01-01	3.75702000000000000
1974-01-01	7.86011000000000100
1975-01-01	17.48470000000000000
1976-01-01	16.12920000000000000
1977-01-01	12.60180000000000000
1978-01-01	14.80640000000000000
1979-01-01	17.23810000000000000
1980-01-01	15.20310000000000000
1981-01-01	13.26810000000000000
1982-01-01	15.83520000000000000
1983-01-01	17.33460000000000000
1984-01-01	19.55830000000000000
1985-01-01	21.23000000000000000
1986-01-01	20.33150000000000000
1987-01-01	18.11380000000000000
1988-01-01	14.36300000000000000
1989-01-01	11.78520000000000000
1990-01-01	9.67108000000000000
1991-01-01	5.42460000000000000
1992-01-01	2.44811000000000000
1993-01-01	2.38267000000000000
1994-01-01	2.08705000000000000
1995-01-01	1.81745000000000000
1996-01-01	1.58266000000000000
1997-01-01	1.33666000000000000
1998-01-01	0.89114699999999990
1999-01-01	0.53903700000000000
2000-01-01	0.32396600000000000
2001-01-01	0.13556100000000000
2002-01-01	0.13290800000000000
2003-01-01	0.13386199999999998
2004-01-01	0.10762700000000000
2005-01-01	0.08143700000000000
2006-01-01	0.07905900000000000
2007-01-01	0.07536699999999999
2008-01-01	0.07090600000000000
2009-01-01	0.06770900000000000
2010-01-01	0.37985399999999997
2011-01-01	0.80667200000000010
2012-01-01	0.91858200000000000
2013-01-01	0.84853799999999990
2014-01-01	0.73022800000000000
2015-01-01	3.48221000000000000
2016-01-01	9.17895000000000000