Private Capital and Digital Infrastructure Development in Nigeria (2001–2025)

Digital infrastructure has emerged as a critical enabler of economic transformation in sub-Saharan Africa, yet its development in Nigeria remains constrained by structural, institutional, and macroeconomic bottlenecks that continue to frustrate investor confidence and policy coherence. This study investigates the relationship between private capital flows and digital infrastructure development in Nigeria over the period 2001–2025, incorporating six control variables: GDP per capita, population density and size, electricity access and power supply, urbanization rate, right-of-way cost, and regulatory quality index, and the security index. Employing an Autoregressive Distributed Lag (ARDL) bounds testing framework, complemented by the Fully Modified Ordinary Least Squares (FMOLS) estimator and the Error Correction Model (ECM), the analysis captures both short-run dynamics and long-run equilibrium relationships. Results indicate that private capital measured through foreign direct investment in the telecommunications sector and private participation in infrastructure exerts a statistically significant and positive long-run effect on digital infrastructure development, proxied by fixed broadband subscriptions per 100 inhabitants, mobile cellular subscriptions, and internet penetration rates. GDP per capita and urbanization rate amplify this relationship, while electricity supply constraints, high right-of-way costs, poor regulatory quality, and deteriorating security conditions significantly dampen private capital's capacity to stimulate digital infrastructure growth. The findings contribute to the sparse empirical literature on private infrastructure finance in frontier markets and offer actionable policy pathways for regulators, institutional investors, and development finance institutions seeking to accelerate Nigeria's digital transition. The study is among the first to systematically incorporate a security index alongside regulatory and structural controls in a time series framework for Nigeria's digital infrastructure sector.