Effets de long terme du taux de change réel sur la balance commerciale nominale et réelle en zone Franc africaine

The purpose of this study is to determine the long-run effects of changes in real exchange rate on the nominal (in value) and real (in volume) trade balance for the countries of the African Franc zone. These countries together have a common currency: the CFA franc, whose parity with the euro is fixed. By applying the cointegration bounds testing approach of Pesaran et al. (2001) on annual data from 1970 to 2006, the study shows, for each of the countries studied, the existence of a long-run relationship between the real trade balance, the real national GDP, real world GDP and the real exchange rate. In addition, the study reverses the empirical validity of the Marshall-Lerner condition for almost all countries of the African Franc zone. On the contrary, the depreciation of the real exchange rate deteriorates the nominal trade balance of these countries. This result could be attributed to the value effect of the depreciation of the real exchange rate, but also to the contraction of the volume effect due to the low competitiveness of exports from these countries, coupled with the strong dependence of their economies in relation to imports of capital goods and equipment and certain consumer goods prized by the population. These last statements are confirmed by the effect on the real trade balance of the depreciation of the real exchange rate which is negative or null for at least 10 of the 14 countries of the African Franc zone