Year	Percent
1960-01-01	51.20670000000000
1961-01-01	52.69470000000000
1962-01-01	51.88070000000000
1963-01-01	53.40320000000000
1964-01-01	57.36270000000000
1965-01-01	56.55340000000000
1966-01-01	58.66840000000000
1967-01-01	63.05460000000000
1968-01-01	70.16140000000000
1969-01-01	80.27580000000000
1970-01-01	79.53150000000000
1971-01-01	76.18550000000000
1972-01-01	77.72290000000000
1973-01-01	79.45070000000000
1974-01-01	94.20299999999999
1975-01-01	108.28299999999999
1976-01-01	100.59800000000000
1977-01-01	96.47140000000000
1978-01-01	101.61100000000000
1979-01-01	98.91799999999999
1980-01-01	80.67690000000000
1981-01-01	71.66310000000000
1982-01-01	75.87830000000000
1983-01-01	79.48270000000000
1984-01-01	82.97190000000000
1985-01-01	83.00070000000000
1986-01-01	85.13260000000000
1987-01-01	86.91320000000000
1988-01-01	90.47390000000000
1989-01-01	93.22570000000000
1990-01-01	92.20880000000000
1991-01-01	63.75120000000000
1992-01-01	37.99130000000000
1993-01-01	37.96250000000000
1994-01-01	39.79330000000000
1995-01-01	71.42020000000000
1996-01-01	94.16830000000000
1997-01-01	91.90330000000000
1998-01-01	90.14890000000000
1999-01-01	88.46180000000000
2000-01-01	86.78350000000000
2001-01-01	83.89410000000000
2002-01-01	82.17330000000000
2003-01-01	83.00890000000000
2004-01-01	83.87010000000000
2005-01-01	86.73720000000000
2006-01-01	91.13610000000000
2007-01-01	94.01100000000001
2008-01-01	93.63630000000000
2009-01-01	82.47220000000000
2010-01-01	76.66630000000000
2011-01-01	84.66320000000000
2012-01-01	88.54700000000001
2013-01-01	83.92580000000000
2014-01-01	78.97000000000000
2015-01-01	80.26960000000000
2016-01-01	85.33360000000000