Shares in Deutsche Bank AG have fallen by more than 48% this year amid concerns that the lender faces a hefty fine from the Justice Department and as its core lending business suffers from low interest rates and weak economic growth.

But some analysts also worry about the exposure at Germany’s largest bank by assets to derivatives and the large pool of hard-to-value assets that the bank holds on its books. Derivatives are financial contracts that draw their value from the performance of an underlying asset, index or interest rate. They can be used to hedge risks.

How vulnerable is Deutsche Bank to derivatives?

In its 2015 annual report, Deutsche Bank said its exposure to derivatives was €41.940 trillion ($46.994 trillion). As a comparison, Germany’s gross domestic product was €3.032 trillion in 2015.

But that raw size can be misleading, since it covers the notional value of the derivatives. For instance, the notional value of an interest-rate swap—the amount from which the payments to each party are calculated—may be large but the actual derivative may cover only small interest payments for either party. That makes the risk to either side much smaller than the figures suggest.