Tariffs and Markups in Retailing

Conventional wisdom suggests that domestic manufacturers benefit from cost advantages vis-a-vis their foreign rivals. Tariffs on imported products or exchange rate depreciations are typically expected to raise relative prices of foreign goods and shift residual demands of domestic substitutes outwards. Here we show that these changes in wholesale/manufacturing prices can be offset and even dominated by adjustments in retail mark-ups. Retailers have an incentive to charge the highest mark-ups for low-cost products, and to adjust the mark-ups on these products most actively. Thus, if the procurement costs of some foreign products rises, retailers will shift these cost increases towards the most efficient domestic products thereby mitigating the benefits of a protectionist tariff. We show that this effect can dominate the traditional substitution effect.