Year	Percent
1969-01-01	33.235700000000000
1970-01-01	24.774000000000000
1971-01-01	23.072100000000000
1972-01-01	22.540500000000000
1973-01-01	20.348800000000000
1974-01-01	17.323400000000000
1975-01-01	19.618500000000000
1976-01-01	20.273400000000000
1977-01-01	20.857400000000000
1978-01-01	19.473600000000000
1979-01-01	18.445800000000000
1980-01-01	17.791400000000000
1981-01-01	19.475000000000000
1982-01-01	19.526000000000000
1983-01-01	20.120500000000000
1984-01-01	20.726200000000000
1985-01-01	20.211900000000000
1986-01-01	20.155800000000000
1987-01-01	20.910600000000000
1988-01-01	22.546400000000000
1989-01-01	21.813200000000000
1990-01-01	25.470000000000000
1991-01-01	29.094300000000000
1992-01-01	31.162400000000000
1993-01-01	34.883900000000000
1994-01-01	37.217500000000000
1995-01-01	38.732100000000000
1996-01-01	39.509100000000000
1997-01-01	42.663300000000000
1998-01-01	47.461999999999996
1999-01-01	47.540400000000000
2000-01-01	49.969200000000000
2001-01-01	52.113700000000000
2002-01-01	50.593400000000000
2003-01-01	52.824300000000000
2004-01-01	54.757700000000000
2005-01-01	55.489700000000000
2006-01-01	58.746900000000000
2007-01-01	61.447500000000000
2008-01-01	67.583800000000000
2009-01-01	73.234400000000000
2010-01-01	73.960100000000000
2011-01-01	76.602400000000000
2012-01-01	72.417000000000000
2013-01-01	71.173300000000000
2014-01-01	71.226200000000000
2015-01-01	69.711100000000000
2016-01-01	72.355800000000000