Financial Inclusion and Economic Growth in Nigeria: An Empirical Article Comparing the Saving-Usage and Credit-Usage Dimensions of Financial Inclusion in Nigeria Using ARDL Bounds Testing

This article re-examines the long-standing but empirically unsettled claim that financial inclusion drives economic growth in Nigeria, by comparing two usage dimensions of inclusion that the literature routinely conflates into a single construct: saving usage, proxied here by Financial Usage/Saving Activity (FUSA, measured by aggregate deposit and savings mobilization as an indicator of active saving behaviour), and credit usage, proxied by credit extended to the private sector. Both are usage-side indicators; unlike physical access measures such as branch counts, a Nigerian saver today can build a FUSA balance through mobile banking platforms such as OPay and Moniepoint, or through POS-agent channels, without ever entering a physical bank branch, which is precisely why deposit and saving activity is better conceptualized as usage rather than access (Sarma & Pais, 2011; Demirguc-Kunt et al., 2018, 2022). Using annual time-series data spanning 1980–2024 obtained from the Central Bank of Nigeria Statistical Bulletin and the World Bank's World Development Indicators, the study models Gross Domestic Product as a function of FUSA, private sector credit and inflation within an Autoregressive Distributed Lag (ARDL) bounds-testing framework. Augmented Dickey-Fuller tests confirm a mixed order of integration across the series (I(0) for inflation and I(1) for the remaining variables), which justifies the ARDL approach over alternative cointegration techniques. The bounds test (F = 4.054) confirms a long-run equilibrium relationship among the variables. The results show that private sector credit exerts a positive and statistically significant long-run effect on output: a one percent increase in private sector credit is associated with an approximately 0.23 percent increase in GDP. FUSA carries an unexpected negative sign and is statistically insignificant in both the long and short run, contrary to the simple positive prior that saving activity alone should raise output; inflation carries the theoretically expected negative sign but is likewise statistically insignificant. The error-correction term is negative and significant, indicating that roughly 17.3 percent of any deviation from long-run equilibrium is corrected within a year. Diagnostic checks (Breusch-Godfrey, White, Ramsey RESET, CUSUM and CUSUM of Squares, supplemented by HAC-robust standard errors) support the reliability of the estimated model. These findings suggest that Nigeria's financial inclusion agenda has, over four decades, delivered growth primarily through the credit-usage channel rather than through saving usage alone, and that policy attention should shift from expanding saving enrolment toward deepening the productive use of financial services through credit.