Year	Percent
1964-01-01	93.31220000000000
1965-01-01	93.38450000000000
1966-01-01	93.62780000000000
1967-01-01	94.04440000000000
1968-01-01	94.09830000000000
1969-01-01	94.30000000000000
1970-01-01	94.78220000000000
1971-01-01	96.26180000000000
1972-01-01	97.78820000000000
1973-01-01	96.26590000000000
1974-01-01	94.45960000000000
1975-01-01	97.31810000000000
1976-01-01	93.15990000000000
1977-01-01	89.89299999999999
1978-01-01	91.36020000000000
1979-01-01	90.91810000000000
1980-01-01	89.87060000000000
1981-01-01	91.30530000000000
1982-01-01	91.93240000000000
1983-01-01	89.74430000000000
1984-01-01	81.82410000000000
1985-01-01	84.26640000000000
1986-01-01	82.33190000000000
1987-01-01	82.90360000000000
1988-01-01	88.09410000000000
1989-01-01	90.59560000000000
1990-01-01	82.76710000000000
1991-01-01	86.25010000000000
1992-01-01	94.87590000000000
1993-01-01	95.68380000000000
1994-01-01	97.71070000000000
1995-01-01	99.15270000000000
1996-01-01	98.67090000000000
1997-01-01	97.54520000000000
1998-01-01	97.46930000000000
1999-01-01	98.17210000000000
2000-01-01	96.27770000000000
2001-01-01	89.87910000000000
2002-01-01	88.53170000000000
2003-01-01	83.99920000000000
2004-01-01	76.93940000000000
2005-01-01	76.41360000000000
2006-01-01	77.50070000000000
2007-01-01	80.92560000000000
2008-01-01	81.91090000000000
2009-01-01	83.10330000000000
2010-01-01	83.26760000000000
2011-01-01	82.81580000000000
2012-01-01	82.13620000000000
2013-01-01	83.30870000000000
2014-01-01	84.36810000000000
2015-01-01	82.51260000000000