Monetary Tightening and U.S. Bank Fragility in 2023: Mark-to-Market Losses and Uninsured Depositor Runs?

Abstract

We develop a conceptual framework and an empirical methodology to analyze the effect of rising interest rates on the value of U.S. bank assets and bank stability. We mark-to-market the value of banks' assets due to interest rate increases from Q1 2022 to Q1 2023, revealing an average decline of 10%, totaling about $2 trillion in aggregate. We present a model illustrating how asset value declines due to higher rates can lead to self-fulfilling solvency runs even when banks' assets are fully liquid. Banks with high asset losses, low capital, and, critically, high uninsured leverage are most fragile. A case study of the failed Silicon Valley Bank confirms the model insights. Our empirical measures of bank fragility suggest that, in the absence of regulatory intervention, many U.S. banks would have been at risk of self-fulfilling solvency runs.

Keywords: Monetary Tightening, Uninsured Depositors, Solvency Runs, Uninsured Leverage, Silicon Valley Bank, First Republic Bank

JEL Classification: G2, L5