Discerning the Impact of Derivatives on Asset Risk: The Case of Canadian Banks

The Canadian banks have shown remarkable resilience to the financial crisis that intensified in the late 2008. The interesting question is whether this stability is due to their prudent lending practices to limit the original risk exposures or due to effective risk management through hedging by using financial derivatives. In this paper, we implement the option‐theoretic model of Merton to calculate the implied asset risk and discern the impact of these derivatives on the aggregate risk for Canadian banks over the period 1997–2008. An algorithm of iterative procedure is developed to impute asset value and risk from bank stock prices. Our estimates show that the risk for Canadian banks is low and even decreasing till the unfolding of the recent crises in 2008. Further analyses reveal that such low risks are not due to reliance on hedging, nor is it related to trading in derivatives, after disentangling the intertwined effects of hedging and trading. These results suggest that involvements in derivatives, in and of themselves, should not be blamed for causing the bank crises; rather, it is conservatism in controlling original risk exposures that remains fundamental for safeguarding a healthy financial system.