Year	Percent
1960-01-01	17.835100000000000
1961-01-01	14.898500000000000
1962-01-01	12.670300000000000
1963-01-01	13.246200000000000
1964-01-01	13.777100000000000
1965-01-01	15.032900000000000
1966-01-01	15.376900000000000
1967-01-01	16.863400000000000
1968-01-01	17.146200000000000
1969-01-01	18.210200000000000
1970-01-01	19.120100000000000
1971-01-01	18.112800000000000
1972-01-01	18.070400000000000
1973-01-01	18.270100000000000
1974-01-01	17.507200000000000
1975-01-01	18.319800000000000
1976-01-01	19.514000000000000
1977-01-01	18.801000000000000
1978-01-01	16.717600000000000
1979-01-01	12.308800000000000
1980-01-01	11.358900000000000
1981-01-01	12.585700000000000
1982-01-01	15.433400000000000
1983-01-01	16.984400000000000
1984-01-01	15.831500000000000
1985-01-01	14.245000000000000
1986-01-01	15.437200000000000
1987-01-01	16.285999999999998
1988-01-01	14.960300000000000
1989-01-01	13.347400000000000
1990-01-01	13.049400000000000
1991-01-01	13.783900000000000
1992-01-01	13.880200000000000
1993-01-01	13.747900000000000
1994-01-01	13.295400000000000
1995-01-01	12.742100000000000
1996-01-01	15.867700000000000
1997-01-01	18.211000000000000
1998-01-01	13.859800000000000
1999-01-01	13.749900000000000
2000-01-01	13.698200000000000
2001-01-01	14.079500000000000
2002-01-01	12.230200000000000
2003-01-01	12.673700000000000
2004-01-01	13.962200000000000
2005-01-01	17.660700000000000
2006-01-01	21.535000000000000
2007-01-01	25.200200000000000
2008-01-01	28.273100000000000
2009-01-01	32.599400000000000
2010-01-01	36.176300000000000
2011-01-01	40.182500000000000
2012-01-01	45.086000000000006
2013-01-01	49.944200000000000
2014-01-01	56.011800000000000
2015-01-01	57.978400000000000
2016-01-01	60.944300000000000