Year	Percent
1960-01-01	17.900000000000000
1961-01-01	20.700000000000000
1962-01-01	24.550000000000000
1963-01-01	13.700000000000000
1964-01-01	11.233300000000000
1965-01-01	10.862500000000000
1966-01-01	11.520000000000000
1967-01-01	12.841700000000000
1968-01-01	15.421400000000000
1969-01-01	18.943800000000000
1970-01-01	14.926500000000000
1971-01-01	13.077700000000000
1972-01-01	12.212600000000000
1973-01-01	11.934400000000000
1974-01-01	14.399600000000000
1975-01-01	10.345800000000000
1976-01-01	8.071830000000000
1977-01-01	11.046700000000000
1978-01-01	12.985300000000000
1979-01-01	14.918100000000000
1980-01-01	17.298700000000000
1981-01-01	21.496300000000000
1982-01-01	20.933900000000000
1983-01-01	16.090000000000000
1984-01-01	13.327600000000000
1985-01-01	9.728810000000001
1986-01-01	12.054500000000000
1987-01-01	13.160900000000000
1988-01-01	11.444000000000000
1989-01-01	18.636000000000000
1990-01-01	8.058810000000001
1991-01-01	8.547950000000000
1992-01-01	11.758800000000000
1993-01-01	15.261200000000000
1994-01-01	17.097300000000000
1995-01-01	18.515300000000000
1996-01-01	18.033900000000000
1997-01-01	18.764500000000000
1998-01-01	21.039800000000000
1999-01-01	23.203900000000000
2000-01-01	22.446100000000000
2001-01-01	21.232900000000000
2002-01-01	15.374700000000000
2003-01-01	10.846500000000000
2004-01-01	9.011200000000000
2005-01-01	9.358360000000001
2006-01-01	10.289600000000000
2007-01-01	11.302200000000000
2008-01-01	11.266800000000000
2009-01-01	11.880200000000000
2010-01-01	11.007300000000000
2011-01-01	11.843100000000000
2012-01-01	13.392300000000000
2013-01-01	13.857100000000000
2014-01-01	12.662600000000000
2015-01-01	12.737400000000000
2016-01-01	12.315700000000000