Evolution in Bank Complexity

In yesterday’s post, our colleagues discussed the historic changes in financial sector size. Here, we tackle a related question on dynamics—how has bank complexity evolved through time? Recently, academics and policymakers have proposed a variety of strong actions to curb bank complexity, stemming from the view that complex banks are undesirable. While the large banks of today are certainly complex, we lack a thorough understanding of how they got that way. In this post and in our related contribution to the Economic Policy Review (EPR) volume, we focus on organizational complexity, measured by the number and types of entities organized together under common ownership and control. Using a new data set of financial-sector acquisitions, we study the structural evolution of banks and its implications for policy. We argue that banks grew into increasingly complex conglomerates in adaptation to a changing financial sector.