Year	Percent
1960-01-01	23.960100000000000
1961-01-01	22.987600000000000
1962-01-01	22.918900000000000
1963-01-01	21.599700000000000
1964-01-01	20.648300000000000
1965-01-01	21.210800000000000
1966-01-01	21.054900000000000
1967-01-01	20.163800000000000
1968-01-01	20.914200000000000
1969-01-01	21.049500000000000
1970-01-01	20.047400000000000
1971-01-01	21.430600000000000
1972-01-01	22.874400000000000
1973-01-01	21.970200000000000
1974-01-01	21.151100000000000
1975-01-01	21.332300000000000
1976-01-01	24.764500000000000
1977-01-01	28.147200000000000
1978-01-01	30.349500000000000
1979-01-01	32.972700000000000
1980-01-01	31.386999999999997
1981-01-01	31.783900000000000
1982-01-01	32.609800000000000
1983-01-01	33.236200000000000
1984-01-01	34.741300000000000
1985-01-01	35.928500000000000
1986-01-01	37.886700000000000
1987-01-01	38.866100000000000
1988-01-01	38.559900000000000
1989-01-01	38.603700000000000
1990-01-01	38.572600000000000
1991-01-01	39.327400000000000
1992-01-01	40.722300000000000
1993-01-01	40.626600000000000
1994-01-01	41.539700000000000
1995-01-01	41.108700000000000
1996-01-01	40.421700000000000
1997-01-01	42.687900000000000
1998-01-01	44.831900000000000
1999-01-01	45.854300000000000
2000-01-01	50.405900000000000
2001-01-01	53.104900000000000
2002-01-01	57.167500000000000
2003-01-01	58.761300000000000
2004-01-01	59.212100000000000
2005-01-01	60.094100000000000
2006-01-01	61.301400000000000
2007-01-01	64.528900000000000
2008-01-01	69.759600000000000
2009-01-01	71.307700000000000
2010-01-01	69.883000000000000
2011-01-01	73.452000000000000
2012-01-01	73.558600000000000
2013-01-01	73.682300000000000
2014-01-01	74.546600000000000
2015-01-01	74.926600000000000
2016-01-01	73.686300000000000