Year	Ratio
1979-01-01	0.617219984531403
1980-01-01	0.623390018939972
1982-01-01	0.760049998760223
1983-01-01	0.836350023746490
1984-01-01	0.781490027904511
1985-01-01	0.836939990520477
1988-01-01	0.719389975070953
1989-01-01	0.746760010719299
2014-01-01	1.386510014534000
2015-01-01	1.339720010757450
2016-01-01	1.199290037155150