The National Bureau of Statistics (NBS) on Thursday announced that Nigeria’s headline inflation moderated in December 2025, following adjustments to the Consumer Price Index (CPI) methodology in line with international best practices.
According to the NBS, headline inflation stood at 15.15 per cent in December 2025. However, after the re-referencing of the CPI using a 12-month index reference period, the year-on-year inflation rate was recalculated at 17.33 per cent.
In its monthly inflation report, the statistics agency explained that the December 2025 year-on-year inflation rate, including all sub-indexes, was derived by maximising the index reference period. This involved equating the average CPI for the 12 months of 2024 to 100, rather than using a single-month reference period.
The NBS noted that relying on a single-month reference period — where December 2024 equals 100 — would have resulted in an artificial spike in the December 2025 inflation figure due to base effects.
“This artificial spike is methodological, not structural, and does not reflect current inflationary realities,” the bureau said, explaining the decision to adopt the 12-month reference period.
The adjustment, it added, affected the raising factor used for re-referencing the 2024 CPI series, as well as the previously released year-on-year inflation rates for January to November 2025.
The bureau stressed that the approach aligns with international standards, as outlined in the International Monetary Fund (IMF) Consumer Price Index Manual and the ECOWAS Harmonised CPI Manual, both of which recommend index reference period maximisation after a rebasing exercise.
The NBS disclosed that the revised 2024 CPI series and updated inflation rates for January to November 2025 are contained in the Excel tables published alongside the report on its website.
The report further revealed that the CPI rose to 131.2 points in December 2025, representing a 0.7-point increase from 130.5 recorded in November.
On a year-on-year basis, the December 2025 inflation rate was 19.65 percentage points lower than the 34.80 per cent recorded in December 2024, indicating a significant easing of price pressures compared to the same period last year, despite differences in base years.
On a month-on-month basis, headline inflation slowed to 0.54 per cent in December 2025, down from 1.22 per cent in November.
“This indicates that the pace of increase in the average price level in December 2025 was lower than in the preceding month,” the NBS stated.