Year	Percent
1965-01-01	14.356000000000000
1966-01-01	14.648600000000000
1967-01-01	14.857800000000000
1968-01-01	14.942300000000000
1969-01-01	15.331800000000000
1970-01-01	15.657400000000000
1971-01-01	16.391100000000000
1972-01-01	17.888300000000000
1973-01-01	19.021500000000000
1974-01-01	19.885100000000000
1975-01-01	21.394300000000000
1976-01-01	21.114200000000000
1977-01-01	20.227700000000000
1978-01-01	21.292600000000000
1979-01-01	20.129300000000000
1980-01-01	20.096400000000000
1981-01-01	23.149900000000000
1982-01-01	25.574800000000000
1983-01-01	27.177600000000000
1984-01-01	30.158400000000000
1985-01-01	36.363700000000000
1986-01-01	35.739900000000000
1987-01-01	26.409000000000002
1988-01-01	27.428500000000000
1989-01-01	28.223600000000000
1990-01-01	25.132200000000000
1991-01-01	22.578600000000000
1992-01-01	23.394500000000000
1993-01-01	26.504700000000000
1994-01-01	32.354300000000000
1995-01-01	35.069600000000000
1996-01-01	37.568300000000000
1997-01-01	39.881900000000000
1998-01-01	40.640900000000000
1999-01-01	41.879600000000000
2000-01-01	41.991500000000000
2001-01-01	42.807300000000000
2002-01-01	42.982300000000000
2003-01-01	40.814900000000000
2004-01-01	39.931800000000000
2005-01-01	38.225300000000000
2006-01-01	37.768700000000000
2007-01-01	39.792300000000000
2008-01-01	41.212400000000000
2009-01-01	43.157000000000000
2010-01-01	43.903000000000000
2011-01-01	42.084600000000000
2012-01-01	40.608100000000000
2013-01-01	40.696200000000000
2014-01-01	40.257100000000000
2015-01-01	39.243200000000000
2016-01-01	40.166400000000000