IMF-测试西非和中非的购买力平价（PPP）（英）

Testing the Purchasing Power Parity (PPP) in West and Central Africa Abdoul Aziz Wane; Carlos Alberto de Resende; Jing Xie WP/25/119 IMF Working Papers describe research in progress by the author(s) and are published to elicit comments and to encourage debate. The views expressed in IMF Working Papers are those of the author(s) and do not necessarily represent the views of the IMF, its Executive Board, or IMF management. 2025 JUN * The authors would like to thank reviewers from the International Monetary Fund African Department’s Research Advisory Groupand anonymous reviewers. They are grateful to Charalambos Tsangarides for coordinating these comments and suggestions.Errors remain the responsibility of the authors.© 2025 International Monetary Fund WP/25/119IMF Working Paper African Department Testing the Purchasing Power Parity (PPP) in West and Central Africa Prepared by Abdoul Aziz Wane, Carlos Alberto De Resende. Jing Xie June 2025 IMF Working Papers describe research in progress by the author(s) and are published to elicit comments and to encourage debate. The views expressed in IMF Working Papers are those of the author(s) and do not necessarily represent the views of the IMF, its Executive Board, or IMF management. ABSTRACT: This paper employs various empirical methods to test the Purchasing Power Parity (PPP) hypothesis in West and Central Africa, considering countries within the WAEMU, CEMAC, CFA, and ECOWAS currency zones and four possible numeraire currencies—U.S. dollar, euro, renmimbi, and the CFA franc. Using panel and single-country unit-root, cointegration, error-correction techniques, our findings indicate that the numeraire currency matters for evidence in favor of PPP. Results show slightly stronger evidence when the euro is used as the reference compared to other numeraire currencies, although results vary across different methods. Evidence for PPP is also stronger across the currency zones after the 1994 devaluation of the CFA franc, when evindence for PPP using the renminbi as reference is also stronger, suggesting an increasing importance of the renminbi for the economies in West and Central Africa. The paper documents significant differences in price dynamics for the CEMAC and the WAEMU, the two components of the CFA zone, with stronger evidence for PPP found for the WAEMU and reversal speed to PPP faster than the 2-3 years found in the literature. Results also indicate that real exchange rates of the currency zones revert to PPP mainly through adjustments of foreign prices expressed in domestic currencies—which may result from changes in nominal exchange rates of the reference currencies or foreign prices—and less so via adjustements in domestic prices. RECOMMENDED CITATION: Wane, A., de Resende, C., and Xie, J. (2025). “Testing the Purchasing Power Parity (PPP) in West and Central Africa,” IMF Working Paper 25/119. JEL Classification Numbers: F1 (International Economics), F3 (International Finance), F31 (Foreign Excha