Competition and Product Differentiation in the Mexican Credit Card Market

This paper studies competition in the market for credit cards in Mexico. It derives demand functions from a discrete choice model, and interest rates from an imperfect competition model, in both cases with differentiated products. These functions are estimated using panel data with 23 credit limit segments and 18 issuing banks between June 2011 and June 2015. The results indicate that there is imperfect competition with differentiated products, and that cards are closer substitutes when they belong to similar segments. Also, they reveal that interest rates respond to costs, although they also reflect supra-competitive margins. The analysis associates market power with the age of the account, which suggests possible information asymmetries and/or switching costs. In general, lower credit limits have higher rates, but also higher costs and lower margins. The results also contribute to assess potential effects of mergers between issuing banks. Finally, the paper presents some policy recommendations based on this evidence.