Vérification empirique du lien finance-croissance économique : approche non linéaire appliquée aux pays de la cedeao[Empirical verification of the finance-economic growth link: non-linear approach applied to ecowas countries]

In this article, a non-linear approach is used to examine the effects of developing financial structures on the economic growth of West African states. To do this, we use the MMG-system to estimate quadratic models such as those proposed by Gambarta et al. (2014) for dynamic panels. Over the period [1998-2017], we show on the one hand that the marginal effect of the banking industry on economic growth increases initially, reaches a maximum and then gradually decreases. This demonstrates a non-linear relationship between increased banking activities and economic growth within the community, and confirms the findings of Hou and Cheng (2017) with low-income countries. On the other hand, a widening of capital markets positively affects the economic growth of West African countries. Overall, our study shows that the main contribution to weakening growth comes from increased banking activities and not from greater investor access to markets. To ensure stable growth, the West African authorities should focus on supporting expanding markets, strengthening liquidity and moderately controlling banking activities. Also, governments should encourage the writing of scientific articles.