Food Marketing Policy Center Wal-Mart’s Monopsony Power in Local Labor Markets

Despite considerable debate as to Wal-Mart’s impact on retail workers, to date there has been little structural analysis on the topic. This paper measures and tests for Wal-Mart’s monopsony power in local labor markets using a dominant-firm model and data on contiguous U.S. counties where the company operates. Empirical results show that Wal-Mart’s monopsony power over workers varies significantly across the country, being higher in rural counties, particularly in the south. For instance, Wal-Mart’s buying power index in labor markets in rural southern central states is estimated to be 6% or higher while the impact on northeastern states’ wages is negligible. The results suggest that this is not a nationwide problem.