Trade Restrictiveness in the Presence of 'New' Goods

The Trade Restrictiveness Index (TRI) by Anderson and Neary (1994) is an index number aggregating trade distortions in the context of a small open economy. A liberalization process which allows trade in goods not traded in previous periods, implies different sets of goods in the two successive periods over which the TRI is defined; this may introduce a bias, inherent in index numbers. This paper attempts a refinement of the standard TRI to allow for the presence of newly traded goods in the definition of the index. In addition, an implementable expression of the refined TRI is provided.