If you calculated that interest rate, it would be negative. Ten-year German bonds have a negative interest rate. Cash savings pay less than bonds, so money in

If you calculated that interest rate, it would be negative. Ten-year German bonds have a negative interest rate. Cash savings pay less than bonds, so money in a cash account pays an even-more negative rate. The only way banks could pay a higher interest rate would be to bear more risk, but that's how you get a banking crisis.