Year	Percent
1962-01-01	99.007400000000000
1963-01-01	99.823300000000000
1964-01-01	99.691800000000000
1965-01-01	99.765800000000000
1966-01-01	79.081200000000000
1967-01-01	56.779100000000000
1968-01-01	57.494000000000000
1969-01-01	56.346200000000000
1970-01-01	70.378400000000000
1971-01-01	99.934100000000000
1972-01-01	99.971100000000000
1973-01-01	99.979100000000000
1974-01-01	99.991400000000000
1975-01-01	99.990900000000000
1976-01-01	99.990100000000000
1977-01-01	99.198700000000000
1978-01-01	95.048900000000000
1979-01-01	93.851200000000000
1980-01-01	92.206600000000000
1981-01-01	90.475000000000000
1982-01-01	90.106100000000000
1983-01-01	86.446800000000000
1984-01-01	82.294900000000000
1985-01-01	78.384500000000000
1986-01-01	74.814000000000000
1987-01-01	74.530200000000000
1988-01-01	76.198900000000000
1989-01-01	75.608000000000000
1990-01-01	74.295000000000000
1991-01-01	74.243500000000000
1992-01-01	73.910200000000000
1993-01-01	70.949600000000000
1994-01-01	65.808400000000000
1995-01-01	58.416500000000000
1996-01-01	50.486999999999995
1997-01-01	46.841700000000000
1998-01-01	44.644800000000000
1999-01-01	45.930800000000000
2000-01-01	47.725000000000000
2001-01-01	49.639700000000000
2002-01-01	49.003400000000000
2003-01-01	48.030300000000000
2004-01-01	50.063900000000000
2005-01-01	54.000900000000000
2006-01-01	66.673800000000000
2007-01-01	78.907400000000000
2008-01-01	81.465900000000000
2009-01-01	80.402400000000000
2010-01-01	79.565100000000000
2011-01-01	81.738100000000000
2012-01-01	84.348999999999990
2013-01-01	86.049500000000000
2014-01-01	86.776300000000000
2015-01-01	87.300800000000000
2016-01-01	87.672999999999990