Year	Percent
1975-01-01	95.5656
1976-01-01	95.7022
1977-01-01	96.2479
1978-01-01	96.0654
1979-01-01	94.9422
1980-01-01	94.2162
1981-01-01	94.1633
1982-01-01	94.4607
1983-01-01	94.6690
1984-01-01	91.6492
1985-01-01	89.2451
1986-01-01	89.6358
1987-01-01	90.6377
1988-01-01	92.5249
1989-01-01	94.1813
1990-01-01	94.7508
1991-01-01	94.8888
1992-01-01	96.3689
1993-01-01	97.9288
1994-01-01	98.3185
1995-01-01	98.3678
1996-01-01	97.9192
1997-01-01	98.0931
1998-01-01	98.6404
1999-01-01	98.7792
2000-01-01	98.9234
2001-01-01	99.1875
2002-01-01	99.3842
2003-01-01	99.4265
2004-01-01	99.4913
2005-01-01	99.5614
2006-01-01	99.6816
2007-01-01	99.7155
2008-01-01	99.7553
2009-01-01	99.8800
2010-01-01	99.9488
2011-01-01	99.9568
2012-01-01	99.9527
2013-01-01	99.5646
2014-01-01	98.9808
2015-01-01	99.3626