Year	Percent
1973-01-01	90.047999999999990
1974-01-01	72.078200000000000
1975-01-01	56.367900000000000
1976-01-01	42.985700000000000
1977-01-01	37.117300000000000
1978-01-01	34.591700000000000
1979-01-01	31.329200000000000
1980-01-01	26.679700000000000
1981-01-01	28.548400000000000
1982-01-01	29.928700000000000
1983-01-01	32.354500000000000
1984-01-01	30.036900000000000
1985-01-01	29.471400000000000
1986-01-01	33.814400000000000
1987-01-01	36.225800000000000
1988-01-01	38.580100000000000
1989-01-01	40.750700000000000
1990-01-01	43.028000000000000
1991-01-01	41.093300000000000
1992-01-01	42.323700000000000
1993-01-01	48.886800000000000
1994-01-01	52.633900000000000
1995-01-01	52.049400000000000
1996-01-01	53.405800000000000
1997-01-01	58.668800000000000
1998-01-01	61.031800000000000
1999-01-01	62.875800000000000
2000-01-01	65.891000000000000
2001-01-01	73.142200000000000
2002-01-01	73.300800000000000
2003-01-01	68.732100000000000
2004-01-01	69.693800000000000
2005-01-01	62.548200000000000
2006-01-01	68.758000000000000
2007-01-01	71.500300000000000
2008-01-01	75.808300000000000
2009-01-01	87.199900000000000
2010-01-01	93.800800000000000
2011-01-01	94.970500000000000
2012-01-01	92.319800000000000
2013-01-01	83.882000000000000
2014-01-01	72.987000000000000
2015-01-01	62.773999999999994
2016-01-01	58.009200000000000