Year	Ratio
1970-01-01	0.71238
1971-01-01	0.71190
1972-01-01	0.71062
1973-01-01	0.72135
1974-01-01	0.73231
1975-01-01	0.73545
1976-01-01	0.74273
1977-01-01	0.75272
1978-01-01	0.76564
1979-01-01	0.77561
1980-01-01	0.78143
1981-01-01	0.80414
1982-01-01	0.82805
1983-01-01	0.84865
1984-01-01	0.86644
1985-01-01	0.87490
1986-01-01	0.89204
1987-01-01	0.90220
1988-01-01	0.91432
1989-01-01	0.93071
1990-01-01	0.94532
1991-01-01	0.95921
1992-01-01	0.99321
1993-01-01	1.01463
1994-01-01	1.02743
1995-01-01	1.06499
1996-01-01	1.08529
1997-01-01	1.11273
1998-01-01	1.14125
1999-01-01	1.13548
2000-01-01	1.13872
2001-01-01	1.14662
2002-01-01	1.16289
2003-01-01	1.16490
2004-01-01	1.17211
2005-01-01	1.17644
2006-01-01	1.18290
2007-01-01	1.18639
2008-01-01	1.18749
2009-01-01	1.18883
2010-01-01	1.18312
2011-01-01	1.18132
2012-01-01	1.17447
2013-01-01	1.16833
2014-01-01	1.16649
2015-01-01	1.16889
2016-01-01	1.16793