Markups and markdowns

This paper studies the high yet undocumented incidence of firms displaying markups lower than unity, i.e., prices lower than marginal costs, for protracted periods of time. Using a large sample of French manufacturing firms for the period 1990-2007, the paper estimates markups at the firm level and documents in a robust way the extent to which firms exhibit negative price-cost margins. The paper also investigates the relationship between the incidence and persistence of negative price-cost margins and candidate explanations, such as subsidies, strategic behaviour, uncertainty and irreversibility.