Comparative Advantage, Service Trade, and Global Imbalances

The large current account deficit of the U.S. is the result of a large deficit in the goods balance and a modest surplus in the service balance. The opposite is true for Japan, Germany and China. Moreover, I document the emergence from the mid-nineties of a strong negative relation between specialization in export of services and current account balances in a large sample of OECD and developing countries. Starting from these new stylized facts, I propose in this paper a “service hypothesis” for global imbalances, a new explanation based on the interplay between the U.S. comparative advantage in services and the asymmetric trade liberalization process in goods trade versus service trade that took place in the last 15 years. First, I use a structural gravity model to show that service trade liberalization lagged behind goods trade liberalization, and I quantify the extent of this asymmetry. Second, I show that a simple two-period model can rationalize the emergence of current account deficits in the presence of such asymmetric liberalization. The key inter-temporal mechanism is the asymmetric timing of trade policies, which affects savings decisions. Finally, I explore the quantitative relevance of this explanation for global imbalances. A multi-period version of the model, fed with the asymmetric trade liberalization path found in the data, generates a current account deficit of about 1% of GDP (roughly 20% of what was observed in the U.S. in 2006).