Concurrent Capital Buffers in a Banking Group

In this article we simulate how much the capital of a parent bank must be increased above the minimum capital requirement applying to the parent alone as a result of a requirement being imposed on the banking group as a whole, and how the probability of failure of a subsidiary and the group changes after a capital buffer is imposed on the group as a whole and/or the subsidiary. The simulation takes into account the relative sizes of the parent and the subsidiary, the parent’s share in the subsidiary, the similarity between the business models of the parent and the subsidiary, and the preparedness of the parent to support the subsidiary if the latter is in danger of failing.