An Underestimated Problem: Concentration of Large Banks in Europe

The consolidation of the European banking sector could increase again with the health crisis. Its impact on the soundness of the sector and the availability of financing is often discussed, its measurement much less so. However, in this article we draw attention to a problematic aspect of concentration or market power measurements. These are generally based on unconsolidated data, which means that the national market power of groups is ignored. This results in an underestimation that we propose to correct. Our correction, based on SURFI data from the Banque de France, raises the share of assets of the five largest resident banks in the total assets of the French banking sector by about 30 percentage points. This underestimation is not neutral from the point of view of prudential policies: concentration is clearly not the same problem depending on whether it is assessed at 50% or 80%.