Year	Percent
1960-01-01	93.88650000000000
1961-01-01	94.40550000000000
1962-01-01	95.47380000000000
1963-01-01	96.06200000000001
1964-01-01	96.43330000000000
1965-01-01	96.33110000000000
1966-01-01	92.69400000000000
1967-01-01	94.45350000000000
1968-01-01	94.63330000000000
1969-01-01	89.06850000000000
1970-01-01	88.84840000000000
1971-01-01	92.84090000000000
1972-01-01	93.42910000000000
1973-01-01	90.41230000000000
1974-01-01	92.98190000000000
1975-01-01	98.29020000000000
1976-01-01	99.07540000000000
1977-01-01	98.95600000000000
1978-01-01	98.72850000000000
1979-01-01	99.06350000000000
1980-01-01	98.56450000000000
1981-01-01	98.45500000000000
1982-01-01	99.21650000000000
1983-01-01	99.14630000000000
1984-01-01	98.34820000000000
1985-01-01	97.36360000000000
1986-01-01	90.52990000000000
1987-01-01	84.31970000000000
1988-01-01	81.94370000000000
1989-01-01	78.38530000000000
1990-01-01	77.13650000000000
1991-01-01	76.78460000000000
1992-01-01	74.99940000000000
1993-01-01	77.13540000000000
1994-01-01	83.25150000000000
1995-01-01	88.42120000000000
1996-01-01	93.74640000000000
1997-01-01	94.69070000000000
1998-01-01	93.66980000000000
1999-01-01	93.57740000000000
2000-01-01	93.86850000000000
2001-01-01	94.31670000000000
2002-01-01	94.11140000000000
2003-01-01	94.03730000000000
2004-01-01	94.95150000000000
2005-01-01	94.54460000000000
2006-01-01	93.64760000000000
2007-01-01	94.85400000000000
2008-01-01	95.77860000000000
2009-01-01	97.04350000000000
2010-01-01	83.95700000000001
2011-01-01	71.54400000000000
2012-01-01	69.69940000000000
2013-01-01	67.64380000000000
2014-01-01	66.03180000000000
2015-01-01	64.52170000000000
2016-01-01	66.28650000000000