Banks' operating profits have risen sharply in recent years as they have invested in long-term government securities and funded these with deposits for which they have had to pay almost nothing.

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Total deposits rose 12% during the year, enabling Santander to repay 24bn euros of the long-term emergency loans it - along with most other banks in the eurozone - received from the European Central Bank last year.

BBC: Santander profits hit by Spain bad loans