Year	Percent
1960-01-01	70.5472
1961-01-01	70.4843
1962-01-01	70.9767
1963-01-01	72.9727
1964-01-01	75.2082
1965-01-01	77.3845
1966-01-01	79.8123
1967-01-01	79.6026
1968-01-01	78.8195
1969-01-01	82.5816
1970-01-01	83.7385
1971-01-01	80.1447
1972-01-01	79.8522
1973-01-01	83.0433
1974-01-01	86.2590
1975-01-01	84.4840
1976-01-01	81.5784
1977-01-01	82.4541
1978-01-01	84.9878
1979-01-01	87.1701
1980-01-01	85.8906
1981-01-01	81.5102
1982-01-01	76.4429
1983-01-01	74.1747
1984-01-01	75.3874
1985-01-01	76.9789
1986-01-01	77.4983
1987-01-01	78.1397
1988-01-01	79.8088
1989-01-01	80.6113
1990-01-01	79.5517
1991-01-01	76.5100
1992-01-01	74.2832
1993-01-01	74.7868
1994-01-01	78.2183
1995-01-01	81.2907
1996-01-01	81.2110
1997-01-01	80.3311
1998-01-01	78.9851
1999-01-01	77.2837
2000-01-01	77.0348
2001-01-01	76.9177
2002-01-01	76.0768
2003-01-01	76.9126
2004-01-01	79.8245
2005-01-01	82.4505
2006-01-01	83.0547
2007-01-01	81.4811
2008-01-01	78.0054
2009-01-01	69.2296
2010-01-01	63.9776
2011-01-01	63.5039
2012-01-01	61.2026
2013-01-01	60.3811
2014-01-01	60.4350
2015-01-01	61.9524
2016-01-01	63.7126