Year	Ratio
1971-01-01	0.187959998846054
1972-01-01	0.162330001592636
1973-01-01	0.161919996142387
1974-01-01	0.167569994926453
1975-01-01	0.197879999876022
1976-01-01	0.176019996404648
1984-01-01	0.295830011367798
1985-01-01	0.296730011701584
2000-01-01	0.814559996128082
2001-01-01	0.395440012216568
2002-01-01	0.399760007858276