The National Bureau of Statistics (NBS) has disclosed that there are plans to ‘normalise’ Nigeria’s inflation data for December 2025 following a projected spike in the December Consumer Price Index.
Analysts projected a spike in the headline inflation for December as a result of base effects, with projections ranging from 31.4–32.4 per cent year-on-year.
Statistician General of the Federation and Chief Executive Officer of NBS, Adeyemi Adeniran, who made this known during a virtual stakeholders engagement convened by the NBS and the Nigerian Economic Summit Group (NESG) on Monday, explained that the expected spike in inflation is driven by technical base effects linked to the recent rebasing of the inflation series rather than changes in economic fundamentals.
According to him, the projected December spike stems from the rebasing of the CPI, which adopted 2024 as the new base year after a 15-year gap from the previous 2009 base.
Adeniran noted that base effects are a common feature of statistical practice, particularly in index-based measurements.
“Following the rebasing exercise and the methodology adopted for December 2025, a significant artificial spike in the inflation rate is expected, as some analysts have already projected. This spike arises from the base effect, with December 2024 equated to 100 following the rebasing.
“Base effects are common in statistical practice, particularly when comparing data across periods with unusually high or low prices. They are neither unexpected nor unusual.
“However, when such effects occur, especially when they are artificial and arithmetic rather than reflective of structural changes in the economy, it is essential to clearly communicate and explain them to users,” he stated.
Adeniran insisted that transparency and accountability guided the Bureau’s decision to address the issue proactively.
“Transparency requires that we provide a clear picture of actual price changes rather than simply reporting an artificial spike that does not reflect economic realities. This is why we convened this meeting to inform our critical stakeholders and users of our data,” he added.
On his part, the Chief Executive Officer of NESG, Tayo Aduloju, underscored the growing importance of credible inflation data as Nigeria transitions from economic stabilisation to consolidation.
“As the economy shifts from stabilisation reforms to consolidation reforms, the role of official statistics—especially the CPI—becomes not less important, but very, very crucial,” he said, pointing out that preliminary assessments suggest inflation figures could record temporary technical spikes, stressing that such outcomes should be carefully interpreted.
“During periods of acute instability, headline inflation serves as an alarm bell. But as we move from managing crisis to managing growth, CPI statistics must help us understand inflation dynamics properly, not just react mechanically to headlines,” he said.
Aduloju noted that misleading inflation signals during the consolidation phase could undermine hard-won gains.
“In this phase of macroeconomic transition, policy errors can be very costly,” he said. “Credible CPI statistics anchor policy coherence, guide monetary policy calibration, inform fiscal planning, shape wage negotiations, and influence investment decisions,” he added.
