Year	Percent
1960-01-01	82.0485
1961-01-01	76.8944
1962-01-01	72.9908
1963-01-01	68.6995
1964-01-01	65.1501
1965-01-01	67.1762
1966-01-01	71.6392
1967-01-01	82.6403
1968-01-01	93.6572
1969-01-01	93.6435
1970-01-01	90.0164
1971-01-01	87.3301
1972-01-01	86.3468
1973-01-01	87.6956
1974-01-01	87.9427
1975-01-01	88.3457
1976-01-01	89.7885
1977-01-01	92.0729
1978-01-01	90.9564
1979-01-01	87.1024
1980-01-01	84.4656
1981-01-01	80.4954
1982-01-01	78.2274
1983-01-01	80.9063
1984-01-01	81.8678
1985-01-01	80.6548
1986-01-01	81.8444
1987-01-01	81.7258
1988-01-01	77.6222
1989-01-01	74.8760
1990-01-01	73.2042
1991-01-01	74.9954
1992-01-01	79.5524
1993-01-01	78.3882
1994-01-01	80.7425
1995-01-01	86.5100
1996-01-01	89.6285
1997-01-01	92.1562
1998-01-01	93.8501
1999-01-01	95.3171
2000-01-01	96.5600
2001-01-01	91.5473
2002-01-01	86.9921
2003-01-01	85.8436
2004-01-01	85.0536
2005-01-01	85.8053
2006-01-01	87.7939
2007-01-01	90.2602
2008-01-01	91.3903
2009-01-01	90.6549
2010-01-01	88.7577
2011-01-01	87.9331
2012-01-01	88.7803
2013-01-01	89.8777
2014-01-01	90.9106
2015-01-01	91.8081
2016-01-01	92.5895