Year	Percent
1960-01-01	67.89590000000000
1961-01-01	68.50290000000000
1962-01-01	69.04130000000000
1963-01-01	68.53010000000000
1964-01-01	70.15580000000000
1965-01-01	71.35710000000000
1966-01-01	69.25140000000000
1967-01-01	70.45540000000000
1968-01-01	71.22180000000000
1969-01-01	65.16500000000000
1970-01-01	60.06180000000000
1971-01-01	59.17020000000000
1972-01-01	59.19060000000000
1973-01-01	60.45140000000000
1974-01-01	61.63310000000000
1975-01-01	63.27890000000000
1976-01-01	69.38110000000000
1977-01-01	75.70640000000000
1978-01-01	78.41440000000000
1979-01-01	78.58380000000000
1980-01-01	78.37440000000000
1981-01-01	77.60460000000000
1982-01-01	78.94170000000000
1983-01-01	72.93370000000000
1984-01-01	63.97950000000000
1985-01-01	63.94150000000000
1986-01-01	64.07690000000000
1987-01-01	68.20070000000000
1988-01-01	60.79420000000000
1989-01-01	48.28940000000000
1990-01-01	57.90610000000000
1991-01-01	65.72680000000000
1992-01-01	69.15780000000000
1993-01-01	52.09720000000000
1994-01-01	48.26980000000000
1995-01-01	68.63780000000000
1996-01-01	96.76080000000000
1997-01-01	97.58760000000000
1998-01-01	97.09090000000000
1999-01-01	89.00560000000000
2000-01-01	77.31140000000000
2001-01-01	80.79980000000000
2002-01-01	83.21530000000000
2003-01-01	82.53560000000000
2004-01-01	83.31780000000000
2005-01-01	85.76290000000000
2006-01-01	88.27140000000000
2007-01-01	89.93760000000000
2008-01-01	95.06200000000001
2009-01-01	99.15100000000001
2010-01-01	98.80580000000000
2011-01-01	99.00990000000000
2012-01-01	99.14560000000000
2013-01-01	99.25130000000000
2014-01-01	97.91310000000000
2015-01-01	95.92399999999999
2016-01-01	90.92650000000000