Population Growth and Economic Growth in Nigeria: Testing the Malthusian Trap Hypothesis

Abstract

This paper examines the relationship between population growth and economic growth in Nigeria from 1980 to 2024 within a Malthusian analytical framework. Using annual time series data and Autoregressive Distributed Lag and Nonlinear ARDL models, the study estimates both symmetric and asymmetric effects of demographic dynamics on real GDP per capita. Unit root and bounds tests confirm a stable long run cointegrating relationship among the variables. The long run results show that population growth and fertility exert statistically significant negative effects on real GDP per capita, which indicates the presence of demographic pressure on economic performance. Agricultural productivity, capital formation, education, and improvements in life expectancy reduce these adverse effects and support income growth. The nonlinear estimates indicate clear asymmetry, where positive shocks to population growth generate stronger negative impacts on per capita income than the gains associated with population growth slowdowns. Short run dynamics show that demographic shocks reduce income growth immediately, while structural improvements support gradual adjustment toward equilibrium. The findings suggest that Nigeria faces a conditional rather than absolute Malthusian constraint, where rapid demographic expansion constrains income growth when not accompanied by sufficient gains in productivity, human capital, and structural transformation. The study concludes by emphasising the importance of integrated demographic and development policies aimed at moderating fertility, improving agricultural productivity, expanding education, and promoting investment in order to harness the demographic dividend.