Production and Consumption Efficiency Gains from Free Trade
by Steven Suranovic ©1997-2006
The aggregate welfare gains from free trade can be
decomposed into two separate effects: production efficiency gains and consumption
In the adjoining figure we show the autarky and free trade equilibria for France. The autarky production and consumption point occurs at the point A with a level of aggregate utility which corresponds to the indifference curve IAut. The French production and consumption points in free trade are P and C, respectively. In free trade France realizes a level of aggregate utility which corresponds to the indifference curve IFT. The free trade price ratio is given by the slope of the national income line which connects P and C. The aggregate welfare gains from free trade corresponds to the difference in utility between IFT and IAut.
To decompose the aggregate effect we simply introduce a national income line with the same slope as the free trade price ratio and pass it through the original production point A. This income line is tangent to the indifference curve IC. The utility level at IC represents the level of aggregate welfare that would be realized if free trade prices prevailed and if there were no changes in domestic production. Thus, the difference in utility between IC and IAut is the increase in welfare that arises solely due to the change in prices. This increase in welfare is the aggregate consumption efficiency gain from free trade.
The remaining gain from free trade corresponds to the difference between utility levels at IFT and IC. This increase in welfare arises solely due to the shift in production from point A to P which represents the aggregate production efficiency gain from free trade.
Thus movements from autarky to free trade results in both aggregate production efficiency gains and aggregate consumption efficiency gains. One can conclude then that both producers and consumers benefit from free trade. This is true, in the aggregate.
International Trade Theory and Policy Lecture Notes: