Last year's inflation just got rewritten

On 10 February, the Bureau of Labor Statistics released its routine annual seasonal revisions to the consumer price index, and in doing so, quietly rewrote the monetary history of late 2022. The narrative that had fueled a powerful multi-month rally in global risk assets was simple: sequential inflation had collapsed dramatically in the fourth quarter, proving that price stability was returning at an accelerating pace. Yet the revised figures revealed that the celebrated disinflation was largely a seasonal illusion. Monthly core CPI prints for October, November, and December were revised upward, demonstrating that underlying price momentum had barely slowed at all.

Seasonal adjustment factors are designed to strip out predictable calendar distortions—such as holiday shopping spikes or summer travel surges—to reveal the underlying trend. But in the wake of unprecedented pandemic dislocations, standard seasonal algorithms struggled to separate structural shifts from temporary fluctuations.

The Arithmetic Revision

The revised data showed that instead of decelerating to an annualised pace near 3 per cent in late 2022, core inflation had remained firmly entrenched north of 4.5 per cent. The apparent winter disinflation that had seduced financial markets was an artifact of flawed statistical weighting rather than genuine economic demand destruction.

This revision creates profound institutional embarrassment for fixed-income desks that had aggressively priced in an early end to the Federal Reserve’s tightening campaign. Trading strategies predicated on bad data are now being systematically dismantled.

Policy Credibility

For the Federal Reserve, the revisions provide vindication for their stubborn refusal to validate market expectations of rate cuts. Jerome Powell and his colleagues had repeatedly warned that a few months of benign prints did not constitute definitive evidence of victory.

The updated data confirms that inflation persistence is real and sticky. The BLS revisions proved that markets had celebrated a statistical mirage; underlying inflation never surrendered in late 2022, leaving the central bank with no choice but to push policy rates deeper into restrictive territory.