Year	Percent
1960-01-01	71.64880000000000
1961-01-01	72.49120000000000
1962-01-01	73.97100000000000
1963-01-01	75.12370000000000
1964-01-01	76.29210000000000
1965-01-01	77.64730000000000
1966-01-01	79.23840000000000
1967-01-01	80.86390000000000
1968-01-01	82.37799999999999
1969-01-01	83.39600000000000
1970-01-01	83.62820000000000
1971-01-01	85.00460000000000
1972-01-01	86.97330000000000
1973-01-01	88.14120000000000
1974-01-01	89.10100000000000
1975-01-01	89.23920000000000
1976-01-01	89.49490000000000
1977-01-01	89.21570000000000
1978-01-01	88.94790000000000
1979-01-01	89.54290000000000
1980-01-01	91.78340000000000
1981-01-01	93.82850000000000
1982-01-01	95.30720000000000
1983-01-01	95.72060000000000
1984-01-01	95.97640000000000
1985-01-01	95.71370000000000
1986-01-01	91.85610000000000
1987-01-01	92.43310000000000
1988-01-01	95.85210000000000
1989-01-01	96.08570000000000
1990-01-01	96.69410000000000
1991-01-01	98.05710000000000
1992-01-01	98.01120000000000
1993-01-01	96.25850000000000
1994-01-01	96.25430000000000
1995-01-01	97.30970000000000
1996-01-01	97.61930000000000
1997-01-01	98.35240000000000
1998-01-01	98.74350000000000
1999-01-01	98.84580000000000
2000-01-01	98.71740000000000
2001-01-01	98.78790000000000
2002-01-01	98.88610000000000
2003-01-01	98.50770000000000
2004-01-01	99.10530000000000
2005-01-01	99.96790000000000
2006-01-01	99.97320000000000
2007-01-01	99.97960000000000
2008-01-01	99.98310000000000
2009-01-01	99.98400000000000
2010-01-01	99.98020000000000
2011-01-01	99.97500000000000
2012-01-01	99.97840000000000
2013-01-01	99.98130000000000
2014-01-01	99.97990000000000
2015-01-01	99.98320000000000
2016-01-01	99.98850000000000