Year	Percent
1960-01-01	30.48820000000000
1961-01-01	29.27560000000000
1962-01-01	31.59670000000000
1963-01-01	33.37470000000000
1964-01-01	34.97060000000000
1965-01-01	36.86850000000000
1966-01-01	37.35680000000000
1967-01-01	39.44140000000000
1968-01-01	40.62880000000000
1969-01-01	41.88940000000000
1970-01-01	42.43540000000000
1971-01-01	43.79140000000000
1972-01-01	44.40810000000000
1973-01-01	44.93450000000000
1974-01-01	45.25440000000000
1975-01-01	50.03810000000000
1976-01-01	54.16480000000000
1977-01-01	55.62450000000000
1978-01-01	58.87430000000000
1979-01-01	59.58730000000000
1980-01-01	61.90680000000000
1981-01-01	65.36850000000000
1982-01-01	67.69410000000000
1983-01-01	68.05440000000000
1984-01-01	69.39750000000000
1985-01-01	69.69080000000000
1986-01-01	71.14630000000000
1987-01-01	74.23450000000000
1988-01-01	75.65030000000000
1989-01-01	75.50380000000000
1990-01-01	76.44560000000000
1991-01-01	77.61270000000000
1992-01-01	79.04370000000000
1993-01-01	81.05880000000000
1994-01-01	81.30550000000000
1995-01-01	81.76750000000000
1996-01-01	81.85210000000000
1997-01-01	80.66350000000000
1998-01-01	80.66350000000000
1999-01-01	80.66350000000000
2000-01-01	79.88550000000000
2001-01-01	59.47800000000000
2002-01-01	58.98080000000000
2003-01-01	60.27840000000000
2004-01-01	61.17100000000001
2005-01-01	63.33300000000000
2006-01-01	66.06410000000000
2007-01-01	70.21330000000000
2008-01-01	77.88190000000000
2009-01-01	81.85790000000000
2010-01-01	78.57580000000000
2011-01-01	76.52770000000000
2012-01-01	76.50550000000000
2013-01-01	77.14730000000000
2014-01-01	77.68310000000000
2015-01-01	78.40000000000000
2016-01-01	80.56750000000000