Year	Percent
1960-01-01	1.46983000000000000
1961-01-01	1.61402000000000000
1962-01-01	1.54401000000000000
1963-01-01	1.15955000000000000
1964-01-01	1.22912999999999980
1965-01-01	1.41688000000000000
1966-01-01	1.09489000000000000
1967-01-01	0.73942800000000000
1968-01-01	0.52219200000000000
1969-01-01	0.44832700000000003
1970-01-01	0.47891000000000006
1971-01-01	0.65120900000000000
1972-01-01	1.45318000000000000
1973-01-01	2.38453000000000000
1974-01-01	2.67544000000000000
1975-01-01	4.66230000000000000
1976-01-01	12.05520000000000000
1977-01-01	15.81850000000000000
1978-01-01	14.16050000000000000
1979-01-01	22.98860000000000000
1980-01-01	32.90260000000000000
1981-01-01	35.37430000000000000
1982-01-01	36.66420000000000000
1983-01-01	37.59320000000000000
1984-01-01	39.41290000000000000
1985-01-01	34.40310000000000000
1986-01-01	30.32470000000000000
1987-01-01	23.72390000000000000
1988-01-01	15.25890000000000000
1989-01-01	13.63380000000000000
1990-01-01	9.31523000000000000
1991-01-01	5.85621999999999950
1992-01-01	2.79157999999999970
1993-01-01	3.18500999999999970
1994-01-01	4.07310000000000000
1995-01-01	4.74494000000000000
1996-01-01	7.12130000000000000
1997-01-01	10.49080000000000000
1998-01-01	14.72640000000000000
1999-01-01	16.20790000000000000
2000-01-01	15.25320000000000000
2001-01-01	13.72150000000000000
2002-01-01	12.49050000000000000
2003-01-01	12.84970000000000000
2004-01-01	13.56460000000000000
2005-01-01	12.56299999999999900
2006-01-01	11.19760000000000000
2007-01-01	9.03365000000000000
2008-01-01	9.24386000000000000
2009-01-01	11.15980000000000000
2010-01-01	9.86166000000000000
2011-01-01	7.34805000000000000
2012-01-01	7.08650000000000000
2013-01-01	7.17540000000000000
2014-01-01	9.02684000000000000
2015-01-01	9.16811000000000000
2016-01-01	7.98023999999999900