Banks grant long-term loans funded by short-term customer deposits. This maturity transformation earns banks money because long-term interest rates are generally higher than short-term interest rates. At the same time, this exposes banks to the risk that interest rates will rise, forcing them to pay more for deposits in the short term already, whereas they only receive the higher interest on new loans. In the low interest rate environment which has prevailed over the past few years, the premium on assuming interest rate risk has trended downward. At the same time, banks with poor profitability have stepped up their maturity transformation and thus also this risk. This is potentially a sign of a search for yield.