Monopsony Power and Poverty: The Consequences of Walmart Supercenter Openings

Working paper
With Lukas Lehner, Zachary Parolin and Clemente Pignatti.
Published

October 5, 2024

Prior research suggests that Walmart Supercenters exert substantial power over the low-wage labor market, though the consequences of Supercenter openings on household incomes and public finances are less clear. This study uses restricted-access Panel Study of Income Dynamics data from 1970 to 2019 to study how Walmart Supercenter openings affect poverty, tax liabilities, and receipt of income transfers. Using a stacked difference-in-differences approach, we find that the opening of a Supercenter leads to a 2 percentage point (16%) increase in poverty. This increase is channeled through declining annual earnings and persists for 10 years following the Supercenter’s entry. Increases in poverty are particularly strong for younger and less-educated adults, and for adults with pre-treatment incomes below the national median. Moreover, Walmart Supercenter openings lead to a $200 (or 16%) per household per year increase in government income transfers received, and a $920 (or 5%) per household per year decrease in tax revenues.