Year	Percent
1969-01-01	97.30960000000000
1970-01-01	97.33800000000000
1971-01-01	97.36700000000000
1972-01-01	97.00560000000000
1973-01-01	98.50420000000000
1974-01-01	98.69120000000000
1975-01-01	97.22340000000000
1976-01-01	96.14980000000000
1977-01-01	95.89640000000000
1978-01-01	96.64200000000001
1979-01-01	95.75880000000000
1980-01-01	93.45980000000000
1981-01-01	92.90660000000000
1982-01-01	94.68460000000000
1983-01-01	95.00550000000000
1984-01-01	94.23120000000000
1985-01-01	94.86850000000000
1986-01-01	96.07920000000000
1987-01-01	95.30260000000000
1988-01-01	95.04220000000000
1989-01-01	93.92260000000000
1990-01-01	92.25020000000000
1991-01-01	91.99220000000000
1992-01-01	91.58130000000000
1993-01-01	92.63790000000000
1994-01-01	93.33760000000000
1995-01-01	93.13050000000000
1996-01-01	93.50420000000000
1997-01-01	94.56200000000001
1998-01-01	96.75560000000000
1999-01-01	98.05000000000000
2000-01-01	97.39160000000000
2001-01-01	96.29020000000000
2002-01-01	95.91820000000000
2003-01-01	96.76320000000000
2004-01-01	97.18750000000000
2005-01-01	97.12440000000000
2006-01-01	97.15750000000000
2007-01-01	96.04440000000000
2008-01-01	96.23680000000000
2009-01-01	97.35330000000000
2010-01-01	96.99330000000000
2011-01-01	96.46350000000000
2012-01-01	95.72540000000000
2013-01-01	94.42020000000000
2014-01-01	93.60220000000000
2015-01-01	93.80799999999999
2016-01-01	92.97780000000000