Year	Percent
1965-01-01	74.62890000000000
1966-01-01	43.17760000000000
1967-01-01	49.66150000000000
1968-01-01	63.55390000000000
1969-01-01	75.45590000000000
1970-01-01	65.80260000000000
1971-01-01	72.38500000000000
1972-01-01	82.91580000000000
1973-01-01	90.12160000000000
1974-01-01	93.73700000000001
1975-01-01	97.13960000000000
1976-01-01	99.77430000000000
1977-01-01	99.52350000000000
1978-01-01	95.16970000000000
1979-01-01	97.42970000000000
1980-01-01	98.16320000000000
1981-01-01	81.85990000000000
1982-01-01	100.25800000000000
1983-01-01	103.29400000000000
1984-01-01	82.14030000000000
1985-01-01	78.62500000000000
1986-01-01	71.45290000000000
1987-01-01	62.92080000000000
1988-01-01	54.76120000000000
1989-01-01	51.52640000000000
1990-01-01	53.36500000000000
1991-01-01	58.01480000000000
1992-01-01	60.05570000000000
1993-01-01	66.23570000000000
1994-01-01	72.52870000000000
1995-01-01	72.88640000000000
1996-01-01	70.74330000000000
1997-01-01	71.26680000000000
1998-01-01	69.26340000000000
1999-01-01	69.59560000000000
2000-01-01	70.50490000000000
2001-01-01	64.36060000000000
2002-01-01	69.50540000000000
2003-01-01	68.44200000000000
2004-01-01	81.63860000000000
2005-01-01	80.87150000000000
2006-01-01	81.92910000000000
2007-01-01	82.70700000000001
2008-01-01	90.62400000000000
2009-01-01	94.57010000000000
2010-01-01	89.55980000000000
2011-01-01	93.38930000000000
2012-01-01	99.41799999999999
2013-01-01	99.03350000000000
2014-01-01	92.15299999999999
2015-01-01	88.63230000000000