Year	Percent
1960-01-01	93.78010000000000
1961-01-01	92.75020000000000
1962-01-01	92.52740000000000
1963-01-01	93.63010000000000
1964-01-01	94.61170000000000
1965-01-01	95.36480000000000
1966-01-01	95.80440000000000
1967-01-01	96.08660000000000
1968-01-01	96.55730000000000
1969-01-01	96.95600000000000
1970-01-01	97.19170000000000
1971-01-01	97.49260000000000
1972-01-01	97.89140000000000
1973-01-01	98.05120000000000
1974-01-01	98.12160000000000
1975-01-01	97.98360000000000
1976-01-01	98.13570000000000
1977-01-01	98.57640000000000
1978-01-01	98.56790000000000
1979-01-01	98.64970000000000
1980-01-01	98.69130000000000
1981-01-01	98.59700000000001
1982-01-01	98.66360000000000
1983-01-01	98.71970000000000
1984-01-01	98.77250000000000
1985-01-01	98.92560000000000
1986-01-01	98.92560000000000
1987-01-01	98.92030000000000
1988-01-01	98.99000000000000
1989-01-01	99.01760000000000
1990-01-01	99.09730000000000
1991-01-01	99.16720000000000
1992-01-01	99.15040000000000
1993-01-01	99.21670000000000
1994-01-01	99.36050000000000
1995-01-01	99.43890000000000
1996-01-01	99.50340000000000
1997-01-01	99.53880000000000
1998-01-01	99.56380000000000
1999-01-01	99.85020000000000
2000-01-01	99.85520000000000
2001-01-01	99.85370000000000
2002-01-01	99.85380000000000
2003-01-01	99.85350000000000
2004-01-01	99.85290000000000
2005-01-01	99.85240000000000
2006-01-01	99.85170000000000
2007-01-01	99.85020000000000
2008-01-01	99.84920000000000
2009-01-01	99.84860000000000
2010-01-01	99.84750000000000
2011-01-01	99.84580000000000
2012-01-01	99.84550000000000
2013-01-01	99.84310000000000
2014-01-01	99.83960000000000
2015-01-01	98.42230000000000
2016-01-01	94.70460000000000