Diminishing gains from trade across countries: Interaction between trade elasticity and openness

This paper theoretically shows that when the trade elasticity is allowed to be country specific and it increases with trade openness across countries, it is possible for the gains from trade to decrease with trade openness across countries under certain conditions, which we call as the diminishing gains from trade. In order to empirically test this possibility, country-specific trade elasticity measures are estimated by using quarterly time-series data for 40 countries, where the model-implied macroeconomic relationship between the home expenditure share and the real income per capita is employed. The average trade elasticity is estimated about 2.7, with a range between 0.3 and 11.9 across countries, which corresponds to the gains from trade of about 30% for the average country. Instead, when a common trade elasticity of 2.7 is used for all countries, the gains from trade are underestimated by about 8% for the average country, showing the importance of using country-specific trade elasticity measures. In a secondary cross-country analysis, the country-specific trade elasticity estimates are shown to increase and the gains from trade are shown to decrease with trade openness measures. It is implied that there are diminishing gains from trade across countries with respect to their trade openness.