Year	Ratio
1970-01-01	0.72576
1971-01-01	0.72743
1972-01-01	0.73452
1973-01-01	0.75028
1974-01-01	0.76203
1975-01-01	0.77295
1976-01-01	0.77429
1977-01-01	0.79937
1978-01-01	0.81059
1979-01-01	0.81869
1980-01-01	0.82552
1981-01-01	0.82789
1982-01-01	0.83994
1983-01-01	0.83990
1984-01-01	0.84246
1985-01-01	0.84710
1986-01-01	0.84141
1987-01-01	0.84447
1988-01-01	0.86182
1989-01-01	0.87235
1990-01-01	0.89003
1991-01-01	0.90044
1992-01-01	0.91951
1993-01-01	0.93210
1994-01-01	0.93625
1995-01-01	0.94917
1996-01-01	0.95120
1997-01-01	0.96400
1998-01-01	0.97298
1999-01-01	0.98711
2000-01-01	0.99296
2001-01-01	0.99507
2002-01-01	1.02091
2003-01-01	1.02304
2004-01-01	1.03380
2005-01-01	1.04587
2006-01-01	1.06092
2007-01-01	1.06504
2008-01-01	1.06989
2009-01-01	1.07163
2010-01-01	1.07292
2011-01-01	1.07266
2012-01-01	1.09278
2013-01-01	1.10411
2014-01-01	1.11275
2015-01-01	1.11584
2016-01-01	1.12326