Year	Percent
1960-01-01	89.85580000000000
1961-01-01	89.72300000000000
1962-01-01	85.96450000000000
1963-01-01	83.69930000000000
1964-01-01	85.95700000000001
1965-01-01	88.70530000000000
1966-01-01	90.99400000000000
1967-01-01	92.41250000000000
1968-01-01	89.77580000000000
1969-01-01	86.49940000000000
1970-01-01	86.39399999999999
1971-01-01	87.14790000000000
1972-01-01	87.83420000000000
1973-01-01	86.00110000000000
1974-01-01	87.34340000000000
1975-01-01	88.73760000000000
1976-01-01	88.10360000000000
1977-01-01	88.95520000000000
1978-01-01	82.07530000000000
1979-01-01	78.65550000000000
1980-01-01	78.26740000000000
1981-01-01	75.12050000000000
1982-01-01	69.48720000000000
1983-01-01	55.75940000000000
1984-01-01	45.58590000000000
1985-01-01	42.56930000000000
1986-01-01	48.64740000000000
1987-01-01	59.61870000000000
1988-01-01	70.25550000000000
1989-01-01	92.77820000000000
1990-01-01	73.70040000000000
1991-01-01	61.20520000000000
1992-01-01	15.13870000000000
1993-01-01	10.76790000000000
1994-01-01	13.65990000000000
1995-01-01	16.62720000000000
1996-01-01	20.10860000000000
1997-01-01	23.46510000000000
1998-01-01	29.41690000000000
1999-01-01	32.34740000000000
2000-01-01	35.94270000000000
2001-01-01	28.45530000000000
2002-01-01	22.19310000000000
2003-01-01	25.54850000000000
2004-01-01	30.48890000000000
2005-01-01	35.71700000000000
2006-01-01	41.02570000000000
2007-01-01	46.48330000000000
2008-01-01	49.53050000000000
2009-01-01	48.56860000000000
2010-01-01	48.24380000000000
2011-01-01	50.97380000000000
2012-01-01	54.58060000000000
2013-01-01	58.68000000000000
2014-01-01	62.95850000000000
2015-01-01	67.52080000000000
2016-01-01	71.32530000000000