Year	Percent
1960-01-01	22.179200000000000
1961-01-01	20.850600000000000
1962-01-01	20.205800000000000
1963-01-01	22.451500000000000
1964-01-01	19.409000000000002
1965-01-01	19.654900000000000
1966-01-01	20.620400000000000
1967-01-01	21.912100000000000
1968-01-01	20.644600000000000
1969-01-01	22.543500000000000
1970-01-01	23.186900000000000
1971-01-01	21.048600000000000
1972-01-01	23.233500000000000
1973-01-01	24.344500000000000
1974-01-01	15.823500000000000
1975-01-01	18.454300000000000
1976-01-01	18.345900000000000
1977-01-01	18.345900000000000
1978-01-01	18.345900000000000
1979-01-01	18.345900000000000
1980-01-01	18.345900000000000
1981-01-01	18.345900000000000
1982-01-01	18.345900000000000
1983-01-01	18.345900000000000
1984-01-01	18.345900000000000
1985-01-01	18.345900000000000
1986-01-01	18.345900000000000
1987-01-01	18.345900000000000
1988-01-01	18.345900000000000
1989-01-01	18.345900000000000
1990-01-01	18.345900000000000
1991-01-01	18.345900000000000
1992-01-01	18.345900000000000
1993-01-01	18.345900000000000
1994-01-01	18.345900000000000
1995-01-01	18.345900000000000
1996-01-01	18.345900000000000
1997-01-01	18.345900000000000
1998-01-01	18.345900000000000
1999-01-01	18.345900000000000
2000-01-01	18.345900000000000
2001-01-01	18.345900000000000
2002-01-01	18.345900000000000
2003-01-01	18.345900000000000
2004-01-01	18.345900000000000
2005-01-01	18.345900000000000
2006-01-01	20.839700000000000
2007-01-01	20.852100000000000
2008-01-01	20.623600000000000
2009-01-01	32.127300000000000
2010-01-01	33.119800000000000
2011-01-01	31.222400000000000
2012-01-01	30.174700000000000
2013-01-01	30.398700000000000
2014-01-01	33.227800000000000
2015-01-01	41.967200000000000
2016-01-01	42.917200000000000