January 19, 2026/CSL Update

Revised Consumer Price Index (CPI) framework pushes inflation lower in December 2025. The National Bureau of Statistics (NBS) and the Nigerian Economic Summit Group (NESG) convened a stakeholder engagement last week during which authorities outlined planned adjustments to the CPI methodology to better align with international best practices.

A key outcome of the discussions was the decision to revise the index reference period used in the recent rebasing exercise. Specifically, the NBS has shifted from using a single-month reference point (December 2024) as the base for the rebased CPI, to adopting a 12-month average for 2024 as the reference period. Under the previous approach, the December 2024 CPI reading was set at 100.0 index points. However, with the revised methodology, the average CPI level across the entire 2024 is now assigned a value of 100.0 points.

While we acknowledge that the revised approach is consistent with the CPI methodological guidelines of the IMF and ECOWAS, the timing of the adjustment raises questions around its primary motivation. In our view, the change appears largely aimed at avoiding a sharp statistical spike in the year-end inflation print, a risk we had flagged as far back as July last year (see CSL H2 2025 Outlook Report:

“Between stabilisation and strain”, 8 July 2025). Based on the previous framework, December inflation could have risen above the 30.0% mark purely on account of base effects. Indeed, the NBS itself noted during its presentation last week that without the adjustment to the CPI framework, headline inflation at year-end would have printed at around 31.2%. Although we agree that the methodological change was ultimately necessary as we had pointed out before, the move is nonetheless likely to heighten concerns about the credibility of data released by the statistical agency.

Kindly click on the link below to download the full report.

​CSL Macro Report – December 2025 Inflation.pdf​