Year	Percent
1960-01-01	15.150800000000000
1961-01-01	12.294700000000000
1962-01-01	11.721700000000000
1963-01-01	10.717700000000000
1964-01-01	9.515690000000000
1965-01-01	10.812300000000000
1966-01-01	10.403700000000000
1967-01-01	10.972500000000000
1968-01-01	11.725300000000000
1969-01-01	13.373200000000000
1970-01-01	14.971100000000000
1971-01-01	14.723600000000000
1972-01-01	15.553100000000000
1973-01-01	16.995400000000000
1974-01-01	16.958200000000000
1975-01-01	18.161200000000000
1976-01-01	17.314100000000000
1977-01-01	17.586600000000000
1978-01-01	18.556900000000000
1979-01-01	23.287500000000000
1980-01-01	15.535000000000000
1981-01-01	15.668200000000000
1982-01-01	16.518700000000000
1983-01-01	17.755300000000000
1984-01-01	17.324100000000000
1985-01-01	17.302600000000000
1986-01-01	14.937500000000000
1987-01-01	10.067400000000000
1988-01-01	16.983000000000000
1989-01-01	30.896100000000000
1990-01-01	23.941100000000000
1991-01-01	14.315000000000000
1992-01-01	18.543300000000000
1993-01-01	23.105600000000000
1994-01-01	24.926800000000000
1995-01-01	24.693900000000000
1996-01-01	27.854800000000000
1997-01-01	31.397800000000000
1998-01-01	34.772900000000000
1999-01-01	36.832400000000000
2000-01-01	39.835300000000000
2001-01-01	42.184300000000000
2002-01-01	40.570200000000000
2003-01-01	42.102900000000000
2004-01-01	43.569300000000000
2005-01-01	46.653500000000000
2006-01-01	50.100000000000000
2007-01-01	52.575700000000000
2008-01-01	54.512100000000000
2009-01-01	53.393200000000000
2010-01-01	47.313500000000000
2011-01-01	47.671400000000000
2012-01-01	49.531500000000000
2013-01-01	50.638700000000000
2014-01-01	51.799000000000000
2015-01-01	55.346000000000004
2016-01-01	59.259500000000000