Year	Percent
1970-01-01	95.833100000000000
1971-01-01	98.252999999999990
1972-01-01	81.497800000000000
1973-01-01	65.508200000000000
1974-01-01	72.202300000000000
1975-01-01	77.658400000000000
1976-01-01	71.033000000000000
1977-01-01	64.744800000000000
1978-01-01	67.879200000000000
1979-01-01	74.775000000000000
1980-01-01	79.918800000000000
1981-01-01	92.227900000000000
1982-01-01	100.973000000000000
1983-01-01	88.477900000000000
1984-01-01	76.646400000000000
1985-01-01	70.467000000000000
1986-01-01	61.338200000000000
1987-01-01	58.064200000000000
1988-01-01	60.568000000000005
1989-01-01	59.898700000000000
1990-01-01	69.678400000000000
1991-01-01	87.818100000000000
1992-01-01	85.760100000000000
1993-01-01	78.352000000000000
1994-01-01	81.026100000000000
1995-01-01	83.826100000000000
1996-01-01	79.491300000000000
1997-01-01	73.834000000000000
1998-01-01	68.703700000000000
1999-01-01	62.656500000000000
2000-01-01	64.689700000000000
2001-01-01	62.739700000000000
2002-01-01	60.194600000000000
2003-01-01	72.339400000000000
2004-01-01	86.491300000000000
2005-01-01	100.509000000000000
2006-01-01	105.258000000000000
2007-01-01	103.253999999999990
2008-01-01	99.034400000000000
2009-01-01	89.267300000000000
2010-01-01	81.075300000000000
2011-01-01	87.133700000000000
2012-01-01	91.793600000000000
2013-01-01	88.106300000000000
2014-01-01	90.469700000000000
2015-01-01	87.307700000000000
2016-01-01	78.929000000000000