New math gives Nigeria artificial inflation spike

Nigeria's inflation fell to 15.2%, but a temporary artificial spike is forecast for December due to a statistical rebasing of the CPI basket.

Nigeria’s recent inflation data, calculated under a revised methodology, show consumer prices rose by 15.2 percent, down from 17.3 percent in November. However, the National Bureau of Statistics (NBS) has warned of a temporary “artificial spike” in the December 2025 rate. Statistician-General Adeyemi Adeniran explained that this anticipated increase is due to statistical base effects, as December 2024 has been set as the new base period (index 100) following a rebasing exercise. He stressed the spike is purely arithmetic and does not reflect underlying economic pressures. The rebased Consumer Price Index (CPI) now tracks 934 items, up from 700, to better reflect modern consumption patterns. NBS Director Ayo Anthony acknowledged that linking the new series to the old could distort December’s figure, but normalisation will address this. The base effect is a one-off occurrence and will not affect data from January 2026 onward. This comes as the central bank transitions to an inflation targeting framework, aiming to slow price growth to 13 percent next year.