While economists focus on the firmer 'core' inflation, financial markets that trade inflation (like TIPS and swaps) price off the 'headline' number. This headline figure has consistently surprised to the downside for 14 of the last 18 months, creating a bearish dynamic for inflation-linked assets.

A more aggressive Federal Reserve reaction function is interpreted as a tightening signal by inflation markets. This leads to lower inflation break-evens and higher real yields, a counter-intuitive move compared to when the Fed and markets react in tandem to strong economic data.

After accounting for measurement quirks in both CPI and PCE, the podcast's economists converge on an estimate for "true" underlying inflation around 2.7-2.8%. This consensus view suggests that while official measures are noisy, the underlying trend is still meaningfully above the Fed's 2% target.

The gap between Core PCE (3.3%) and Core CPI (2.5%) inflation is driven by how each index weighs shelter and measures financial services. CPI gives more weight to disinflating shelter, while PCE is inflated by a stock market-linked measure for financial services.

Despite a downside surprise in CPI, the Fed's preferred inflation gauge, Core PCE, is still rising. This growing negative wedge between the two metrics leads to a more hawkish Fed policy than CPI alone would suggest, creating a negative outlook for TIPS in the near term.

Recent bond market volatility stems from a Fed credibility issue, not just rate expectations. Uncertainty over which inflation metric the Fed is targeting (e.g., Core PCE vs. Dallas Trimmed Mean) creates ambiguity about its reaction function, fueling investor fear and raising the term premium.

The Fed's primary inflation gauge, Core PCE, is running nearly 100 basis points hotter than Core CPI, the benchmark for inflation markets. This creates a risk of the Fed overtightening policy based on sticky PCE data, which could lead to a weaker-than-expected inflation outcome for CPI and thus cause underperformance for CPI-linked bonds.

A measure of "market-based core PCE services ex-housing" inflation is accelerating. This niche metric, which strips out imputed prices and volatile sectors, suggests that core economic activity is generating persistent inflation, challenging narratives focused solely on energy shocks or trade wars.

The Bureau of Economic Analysis will soon change how it calculates financial services prices for the PCE deflator. It's moving from a stock market-based measure to one based on wages, a change expected to reduce year-over-year Core PCE by 0.1-0.2 percentage points.