Year	Percent
1960-01-01	6.82563000000000000
1961-01-01	6.24643000000000000
1962-01-01	5.45983000000000000
1963-01-01	4.49620000000000000
1964-01-01	3.72574000000000000
1965-01-01	3.96568000000000030
1966-01-01	3.71611999999999960
1967-01-01	3.30950000000000000
1968-01-01	3.47100999999999970
1969-01-01	3.64673000000000020
1970-01-01	3.25294000000000000
1971-01-01	2.11962000000000030
1972-01-01	1.00378000000000000
1973-01-01	0.79239600000000000
1974-01-01	1.25468000000000000
1975-01-01	2.48103000000000000
1976-01-01	4.17077000000000000
1977-01-01	4.92071999999999900
1978-01-01	4.56488000000000050
1979-01-01	4.62160999999999960
1980-01-01	4.70519000000000000
1981-01-01	4.45058000000000000
1982-01-01	3.33235000000000000
1983-01-01	2.03910000000000000
1984-01-01	2.15257000000000000
1985-01-01	2.91237000000000000
1986-01-01	3.32481000000000000
1987-01-01	2.85968000000000000
1988-01-01	1.95645000000000000
1989-01-01	1.28057999999999980
1990-01-01	1.07446000000000000
1991-01-01	1.17499000000000000
1992-01-01	2.27087000000000000
1993-01-01	3.13772000000000030
1994-01-01	2.87586000000000000
1995-01-01	3.06318000000000000
1996-01-01	4.45381000000000000
1997-01-01	4.25623000000000000
1998-01-01	3.48348000000000000
1999-01-01	3.02438000000000000
2000-01-01	2.46202000000000000
2001-01-01	2.69024000000000000
2002-01-01	2.66520999999999960
2003-01-01	2.02710000000000000
2004-01-01	1.71200000000000000
2005-01-01	2.20076000000000000
2006-01-01	2.96445000000000000
2007-01-01	4.29356000000000000
2008-01-01	6.33843000000000100
2009-01-01	5.82126999999999900
2010-01-01	3.33955999999999960
2011-01-01	3.15107000000000030
2012-01-01	3.45290999999999970
2013-01-01	1.98262000000000000
2014-01-01	0.49092700000000006
2015-01-01	0.53554799999999990
2016-01-01	0.72109899999999990