Year	Ratio
1970-01-01	0.60716
1971-01-01	0.60803
1972-01-01	0.61517
1973-01-01	0.62174
1974-01-01	0.61651
1975-01-01	0.61979
1976-01-01	0.62562
1977-01-01	0.63407
1978-01-01	0.63289
1979-01-01	0.64371
1980-01-01	0.64881
1981-01-01	0.66199
1982-01-01	0.66905
1983-01-01	0.66423
1984-01-01	0.67485
1985-01-01	0.68626
1986-01-01	0.70351
1987-01-01	0.71123
1988-01-01	0.72690
1989-01-01	0.71568
1990-01-01	0.72894
1991-01-01	0.74984
1992-01-01	0.75993
1993-01-01	0.78467
1994-01-01	0.79440
1995-01-01	0.79774
1996-01-01	0.80649
1997-01-01	0.81440
1998-01-01	0.82070
1999-01-01	0.82623
2000-01-01	0.83363
2001-01-01	0.84342
2002-01-01	0.85754
2003-01-01	0.93824
2004-01-01	0.93454
2005-01-01	0.94751
2006-01-01	0.95547
2007-01-01	0.96262
2008-01-01	0.98379
2009-01-01	0.99526
2010-01-01	0.99516
2011-01-01	1.00467
2012-01-01	1.00902
2013-01-01	1.06483
2014-01-01	1.06078
2015-01-01	1.06524
2016-01-01	1.09520