Tariff Reductions, Entry, and Welfare : Theory and Evidence for the Last Two Decades

In a standard multi-sector, heterogeneous-firm trade model the effect of tariffs on entry, especially in the presence of production linkages, can reverse the traditional positive optimal-tariff argument. We construct and employ a new, large, disaggregated tariff dataset and then apply a 189-country, 15-sector version of our model in order to quantify the trade, entry, and welfare effects of trade liberalization over the period 1990-2010. We find that the impact on firm entry was larger in Advanced Economies relative to Emerging and Developing Economies; that more than 90% of the gains from trade are a consequence of the reductions in MFN tariffs (the Uruguay Round); and that for some countries, particularly some Emerging and Developing Economies, there are additional gains from a further move to complete free trade. The countries which would gain from the elimination of tariffs have a strong rank correlation with those that gain from a negative optimal tariff, which comprise one-quarter of the countries in the world