GTAP Data Bases: Trade Data
Mark Gehlhar is a member of the GTAP Research Fellow Hall of Fame. He has been involved with GTAP since its inception in the early 1990's--first as a graduate student, and then as an Economist with the Economic Research Service (ERS/USDA).
Mark Gehlhar leads the reconciliation of the bilateral trade data used in GTAP. Many of us take for granted the fact that the trade data in the GTAP Data Base is accurate and balances, but those who have worked with the raw trade data know there are many pitfalls. Mark's approach to this seemingly intractable problem has earned him praise from many quarters and his contribution of the bilateral trade matrix is a key input into the construction of each new GTAP Data Base.
What’s New in Global Merchandise Trade?
Since 2001, the base year for the version 6 database, world merchandise trade has doubled souring more than $12 trillion in 2006. Global trade is maintaining an unprecedented pace with China as a key driver. China’s exports are now 4 times greater than in 2001 with greater diversification of partners. While rapid trade growth alone does not present a problem for constructing new releases for the database for GTAP, new complexities associated with shifting production and entropy trade add challenges for solving source and destination puzzles. Emerging markets such as India, Mexico, Kazakhstan, Russia, Turkey, and Vietnam are quickly moving up the ranks trading partners. There is a growing incidence of inexplicably discrepancies associated with particular industries and nontraditional trading partners for China. New initiatives have been launched to better understand reasons for discrepant trade and procedures for improving data quality. An organized session addressing this issue was held at the 10th Annual Conference on Global Economic Analysis in June 2007.
Status of Reporting Country Coverage
The GTAP trade data has relied nearly entirely on publicly available trade records. There are at most 170 countries that that release records using internationally acceptable nomenclature. Not all reporters in 2001 were available in 2004 and not all countries reported used the Harmonized System (HS) classification. For example, Vietnam and the United Arab Emirates still reported trade using the Standard International Trade Classification SITC trade classification. The lack of uniform reporting classification frustrates assemble process of raw data for GTAP since both classification system must be used. The SITC system does map as precisely to the GTAP sector classification. Another problem is the unspecified or unidentified partners. The reasons for unspecified trade vary from country to country. Certain industries Australian exports have for many years remained confidential where goods or partners are unknown. Oil and petroleum products and commonly not specified.
Country Reporting Status for Imports 2003-2005
Country Reporting Status for Exports 2003-2005
Africa Trade: Likely Significant Flows Missing
Documentation
New Issues with the Trade Data
- Re-exports: These are a big issue for a number of countries. With the help of Zhi Wang at the USITC and the CPB in the Netherlands, Mark Gehlhar is improving the way in which re-exports are treated for Hong Kong and The Netherlands.
- Latin American Trade: Mark is also working with the IADB to improve the trade data for Latin America.
Those interested in contributing to the trade data, should contact Mark Gehlhar.
Last Modified: 1/8/2021 3:04:11 PM
