Spatial Dynamics, Convergence, and Persistence of Inflation in Post-Rebasing Nigeria: Evidence from State-Level CPI Indices (2024–2025)

Following the 2024 rebasing of Nigeria’s Consumer Price Index (CPI), understanding the spatial and temporal behavior of inflation at the sub-national level has become critical for evidence-based macroeconomic and food-security policy. This study investigates the spatial dynamics, convergence properties, and persistence of inflation across Nigeria’s 36 states and the Federal Capital Territory using newly rebased state-level CPI data for February 2024–November 2025. Headline (All-Items) and Food CPI series were analyzed to capture both general price movements and food-specific pressures. Methodologically, the study integrates spatial econometrics and panel convergence analysis. Spatial dependence and cross-border spillovers were assessed using Global Moran’s I, Local Indicators of Spatial Association (LISA), and spatial regression models (SAR, SEM, SDM). Inflation convergence was examined through σ-convergence (cross-sectional dispersion over time) and β-convergence (catch-up dynamics based on initial price levels). Finally, inflation persistence and regime shifts were evaluated using state-specific AR(1) models and Bai–Perron structural break tests. Results reveal weak global spatial autocorrelation but the presence of localized inflation hot-spots and cold-spots, particularly in northern states (e.g., Kebbi, Sokoto, Zamfara) and Rivers State. σ-convergence results indicate sharp short-term divergence in 2025, especially for food inflation, while β-convergence estimates provide strong evidence of long-run price-level convergence across states. Persistence analysis shows predominantly negative or insignificant AR(1) coefficients, implying that post-rebasing inflation shocks are largely mean-reverting and short-lived, with widespread structural breaks concentrated in early 2024.