Sorting Out the Bilateral Trade and Income Convergence Relationship: Does Income and the Nature of Bilateral Trade Matter?

Several studies have used various datasets and methodologies to analyze the relationship between bilateral trade and income convergence among trading partners. However, most studies have not paid attention to the effect that income levels and nature of bilateral trade have on the speed of income convergence. In this paper, we argue that the income levels of trading partners and the nature of bilateral trade play important role in the relationship between bilateral trade and international income convergence. To account for the effect of income levels of trading partners, this paper presents an approach that explicitly accounts for bilateral trade among high-income (OECD) countries, bilateral trade between high-income and low-income (SSA) countries, and bilateral trade among low-income (SSA) countries. We also used total trade data for 25 OECD countries and 30 Sub-Saharan African countries over the period 1980-2018 to avoid the potential bias for selecting certain countries based on arbitrary percentage of trade relationship. We used the 2SLS estimations technique to avoid endogeneity problems due to the nature of the dataset. The paper finds that the bilateral trade-income convergence relationship for OECD to SSA is the strongest. This result throws light on the claim that the nature of bilateral trade between high-income and low-income countries promotes one directional knowledge spillover from high-income to low-income countries which enables low-income countries to adopt new technologies and grow faster than their high-income counterparts. Also, bilateral trade among OECD countries, which mostly comprises of differentiated products, promotes descent income convergence among them. However, bilateral trade among SSA countries has the least effect on income convergence. Findings of the study have important implications for bilateral trade among low-income countries and between low income and high income countries. First, if SSA countries want to develop and catch up with their rich counterparts, they should continue to promote free trade with high income countries by dismantling remaining protection policies. Second, the African Continental Free Trade Area’s (AfCFTA) efforts to boost the manufacturing sector through industrialization is in the right direction to promote the production of more differentiated products in Africa which will create growth in income for member countries as they trade more. Finally, there is the need for SSA countries to increase investment rates and improve human capital accumulation to enable them to accelerate the adoption of new technologies and grow faster than their high-income counterparts, while bridging the income gap between them through trade.