Year	Percent
1962-01-01	98.54600000000000
1963-01-01	95.75980000000000
1964-01-01	94.17180000000000
1965-01-01	94.78940000000000
1966-01-01	92.67770000000000
1967-01-01	93.02320000000000
1968-01-01	98.05370000000000
1969-01-01	99.97880000000000
1970-01-01	99.99100000000000
1971-01-01	99.99160000000000
1972-01-01	99.98490000000000
1973-01-01	99.99330000000000
1974-01-01	99.99330000000000
1975-01-01	99.99330000000000
1976-01-01	99.99840000000000
1977-01-01	97.92790000000000
1978-01-01	95.24500000000000
1979-01-01	93.99830000000000
1980-01-01	93.23620000000000
1981-01-01	92.88740000000000
1982-01-01	91.17190000000000
1983-01-01	88.63570000000000
1984-01-01	87.03750000000000
1985-01-01	87.76660000000000
1986-01-01	89.27690000000000
1987-01-01	87.99770000000000
1988-01-01	87.13890000000000
1989-01-01	88.46700000000001
1990-01-01	89.24450000000000
1991-01-01	87.41920000000000
1992-01-01	84.02400000000000
1993-01-01	81.13450000000000
1994-01-01	75.16270000000000
1995-01-01	68.07470000000000
1996-01-01	65.90240000000000
1997-01-01	68.77790000000000
1998-01-01	70.07120000000000
1999-01-01	68.44450000000000
2000-01-01	68.44470000000000
2001-01-01	71.67640000000000
2002-01-01	74.91380000000000
2003-01-01	78.45980000000000
2004-01-01	81.56730000000000
2005-01-01	84.55690000000000
2006-01-01	89.96060000000000
2007-01-01	93.91700000000000
2008-01-01	94.46710000000000
2009-01-01	91.56930000000000
2010-01-01	89.30430000000000
2011-01-01	90.81690000000000
2012-01-01	91.32900000000000
2013-01-01	92.16270000000000
2014-01-01	93.72200000000001
2015-01-01	94.52540000000000
2016-01-01	94.61210000000000