One good inflation report does not make a trend

The release of the October consumer price index on 10 November ignited the most ferocious global asset rally of the year. Headline inflation rose by 7.7 per cent year-on-year, down from 8.2 per cent in September, while core inflation stepped down to 6.3 per cent. In response, equity markets surged as if price stability had been restored overnight; the S&P 500 jumped 5.5 per cent in its best single-day performance since the depths of the 2020 pandemic, and two-year Treasury yields plunged by nearly thirty basis points. Yet the celebratory mood across trading desks relies on a profound analytical mistake: conflating a single month of statistical deceleration with the structural end of an inflationary regime.

Financial markets have spent the past eighteen months repeatedly jumping at the shadows of imaginary inflation peaks. Every moderate monthly print is greeted by macro traders as the definitive pivot signal that will allow the Federal Reserve to pause its tightening cycle and return to balance-sheet expansion. Such optimism reflects a fundamental misunderstanding of the central bank's reaction function. Central bankers do not calibrate monetary policy against a single data point; they calibrate against the persistent, underlying momentum of core service prices. On that front, the war is far from won.

The Anomaly of Used Cars

A dispassionate inspection of the October report reveals that the bulk of the disinflationary relief was concentrated in narrow, highly volatile physical goods components. The single largest contributor to the downside surprise was a 2.4 per cent month-on-month collapse in used car and truck prices, accompanied by a sharp deceleration in medical care services that was driven entirely by an annual administrative adjustment in health insurance accounting rather than an actual reduction in doctor bills.

Used car prices, which had surged to absurd premiums during the semiconductor shortages of 2021, are simply reverting to historical depreciation curves as dealer inventories normalise. This is textbook supply-side healing, and it is undoubtedly welcome. However, supply-chain normalisation in traded physical goods is a finite, one-off adjustment. Once used vehicle prices have adjusted back toward their pre-pandemic baseline, the mathematical tailwind they provide to the headline index will vanish entirely.

The Inelastic Service Wall

Meanwhile, the true engine of underlying inflation—core services ex-energy—continued its uncomfortably steady compounding. Shelter costs, which represent nearly one-third of the total consumer price basket, surged by 0.8 per cent on the month, the largest single-month advance since 1990. While market-based measures of new apartment leases have begun to cool, the official shelter index operates on a twelve-month rolling collection methodology that guarantees persistent, elevated prints well into 2023.

More critically, service prices outside of shelter remain directly tethered to nominal wage growth. With the domestic labour market still operating at an unemployment rate of 3.7 per cent and average hourly earnings expanding at an annual rate of 4.7 per cent, service providers possess both the operational incentive and the pricing power to pass higher labour bills directly onto customers. A central bank that relaxes financial conditions prematurely risks allowing this domestic wage-price dynamic to harden into permanent inflation expectations.

The market rally that followed the October CPI print was an unhedged act of collective self-indulgence. By driving equity multiples higher, narrowing corporate bond spreads, and knocking twenty-five basis points off terminal rate pricing, traders engineered a massive easing of financial conditions that directly contradicts the Federal Reserve’s objectives. Policymakers will not permit market exuberance to dismantle their hard-won disinflationary progress; they will respond by pushing terminal rate expectations higher for longer until the underlying service trend conclusively breaks.