Year	Percent
1960-01-01	50.31320000000000
1961-01-01	52.76760000000000
1962-01-01	55.87130000000000
1963-01-01	56.28190000000000
1964-01-01	56.96470000000000
1965-01-01	59.58860000000000
1966-01-01	62.81340000000000
1967-01-01	65.85060000000000
1968-01-01	69.28910000000000
1969-01-01	72.72740000000000
1970-01-01	77.81590000000000
1971-01-01	81.91030000000000
1972-01-01	82.78970000000000
1973-01-01	83.23260000000000
1974-01-01	84.47550000000000
1975-01-01	85.02240000000000
1976-01-01	83.17320000000000
1977-01-01	82.71480000000000
1978-01-01	83.10160000000000
1979-01-01	80.78270000000000
1980-01-01	80.70930000000000
1981-01-01	80.28100000000000
1982-01-01	78.00480000000000
1983-01-01	76.02000000000000
1984-01-01	73.52840000000000
1985-01-01	71.77270000000000
1986-01-01	71.95130000000000
1987-01-01	71.77420000000000
1988-01-01	67.01140000000000
1989-01-01	61.28040000000000
1990-01-01	60.93060000000000
1991-01-01	65.18940000000000
1992-01-01	70.16960000000000
1993-01-01	74.29980000000000
1994-01-01	78.17090000000000
1995-01-01	81.15190000000000
1996-01-01	81.27190000000000
1997-01-01	82.36060000000000
1998-01-01	85.12220000000000
1999-01-01	86.29899999999999
2000-01-01	87.18820000000000
2001-01-01	87.38120000000000
2002-01-01	85.76799999999999
2003-01-01	83.62410000000000
2004-01-01	82.34170000000000
2005-01-01	83.16030000000000
2006-01-01	85.09890000000000
2007-01-01	86.33050000000000
2008-01-01	87.63230000000000
2009-01-01	87.88900000000000
2010-01-01	87.39960000000000
2011-01-01	87.03070000000000
2012-01-01	86.91820000000000
2013-01-01	86.05160000000000
2014-01-01	87.13770000000000
2015-01-01	88.80740000000000
2016-01-01	89.25120000000000