An important IMF working paper, released today suggests that the standard stress test models used to assess risks in the banking system are likely to underestimate the impact of stress on bank solvency and financial stability because they do not consider the dynamics between solvency and funding costs.
The global financial crisis appears to have been a liquidity crisis, not just a solvency crisis. Yet the failure to adequately model interlinkages and the nexus between solvency risk and liquidity risk led to a dramatic underestimation of risks. Liquidity risk manifests primarily through a liquidity crunch as firms’ access to funding markets is impaired, or a pricing crunch, as lenders are unwilling to lend unless they receive much higher spreads.
A sudden increase in bank funding costs can have an adverse impact on financial stability through the depletion of banks’ capital buffers. To preserve financial stability, it is important to assess banks’ vulnerability to changes in funding costs. The reason is twofold. First, to the extent funding costs reflect counterparty credit risk, it is of particular interest for supervisors to determine the level of capital buffers that should be held to keep funding costs at bay if and when market conditions deteriorate. Second, funding costs are linked not only to banks’ initial capital position but also they determine their capital position going forward, paving the way for adverse dynamics. The magnitude of this effect is likely to depend on the bank’s behavioral reaction to rising funding costs. On the one hand, it may react by setting higher lending rates to its borrowers. Yet this action reduces the bank’s market share and its franchise value. On the other hand, the bank might not be able to passthrough additional funding costs to new lending so its internal capital generation capacity is reduced. Even if some pass-through is possible, the erosion of profits is likely to be
substantial given the shorter time to repricing of liabilities relative to assets with the margin impact on the carrying values of assets outweighing that of new asset generation.“Bank Solvency and Funding Cost: New Data and New Results” presents new evidence on the empirical relationship between bank solvency and funding costs. Building on a newly constructed dataset drawing on supervisory data for 54 large banks from six advanced countries over 2004–2013, we use a simultaneous equation approach to estimate the contemporaneous interaction between solvency and liquidity. Our results show that liquidity and solvency interactions can be more material than suggested by the existing empirical literature. A 100 bps increase in regulatory capital ratios is associated with a decrease of bank funding costs of about 105 bps. A 100 bps increase in funding costs reduces regulatory capital buffers by 32 bps. We also find evidence of non-linear effects between solvency and funding costs. Understanding the impact of solvency on funding costs is particularly relevant for stress testing. Our analysis suggests that neglecting the dynamic features of the solvency-liquidity nexus in the 2014 EU-wide stress test could have led to a significant underestimation of the impact of stress on bank capital ratios.
The results are also highly relevant for cost impact assessments of capital regulation, as the costs of higher capital requirements are partly offset by lower debt servicing costs.
Note: IMF Working Papers describe research in progress by the author(s) and are published to elicit comments and to encourage debate. The views expressed in IMF Working Papers are those of the author(s) and do not necessarily represent the views of the IMF, its Executive Board, or IMF management.
