Why the Fed Targets Core PCE Inflation, Not CPI, to Set Interest Rates

When the Federal Reserve decides whether to raise, lower, or hold interest rates, it watches the Personal Consumption Expenditures price index—not the Consumer Price Index that dominates headlines. The Federal Open Market Committee adopted PCE as its official inflation target in February 2000 and has used it ever since to gauge whether inflation is consistent with the Fed's mandate for price stability and maximum employment.

The gap between core PCE and core CPI has run about three-tenths of a percentage point on average over two decades, a difference driven mainly by how broadly each index measures healthcare spending and what weighting method each uses. This gap is not technical minutiae: because the Fed targets PCE, not CPI, the specific inflation reading from PCE shapes whether policymakers see a persistent inflation problem calling for higher interest rates or a moderating situation allowing for eventual rate cuts.

How the Bureau of Economic Analysis builds the PCE price index

The Personal Consumption Expenditures price index is constructed monthly by the Bureau of Economic Analysis from invoices, scanner data, and survey responses collected directly from businesses—retailers, insurers, hospitals, and employers—rather than from household price reports. This business-side sourcing allows the BEA to capture what consumers actually spend more quickly than household surveys can, and it includes spending that households don't directly see: employer contributions to health insurance, government health programs, and other business-funded services.

The BEA uses a Fisher Price Index formula, a chained method that recalculates the weights of each category monthly to reflect actual changes in consumer spending patterns. If beef prices rise and consumers shift to buying more chicken, the index automatically increases chicken's weight in the next month's calculation. The CPI, by contrast, locks in its weights annually and measures prices against a fixed basket, designed to show what a constant purchase would cost rather than what consumers actually buy. This dynamic weighting method means PCE tends to produce lower inflation readings than CPI, because it captures the real substitution effect that occurs when relative prices shift.

Why core PCE runs lower than core CPI

Core PCE and core CPI both exclude volatile food and energy categories to focus on underlying price pressures. Over the past two decades, core CPI has run about 30 basis points—roughly three-tenths of a percentage point—higher than core PCE on average. This persistent wedge reflects differences in methodology and scope between the two indexes.

Healthcare is the largest source of the divergence. Core PCE includes all healthcare spending: what patients pay out of pocket, what employers contribute to employee health insurance, and what Medicare and Medicaid pay providers. Core CPI measures only out-of-pocket household spending. Core PCE gives healthcare a much larger weight than core CPI does. Because healthcare inflation often moves at a different pace than overall consumer prices, this weighting difference produces a substantial gap between the two measures. Differences in how the agencies price airfares and other services account for additional divergence.

Technical revisions and their policy implications

The Bureau of Economic Analysis periodically revises its PCE calculation methodology to reflect new data sources or improved measurement techniques. Effective September 30, 2026, the BEA changed how it prices portfolio management and investment advice services, replacing a producer-price-based deflator with one derived from employment data.

For the Federal Reserve, PCE methodology revisions carry real policy weight. The Fed watches month-to-month and year-over-year PCE changes closely when deciding whether to adjust interest rates. Small shifts in the index can swing the interpretation of whether inflation is tightening or loosening. Because the Committee has committed to the 2 percent core PCE target as its long-run inflation goal, revisions that lower recent readings can influence whether the Fed sees room to pause rate increases or must continue tightening.

Why the Fed's choice of PCE shapes interest rate decisions

The Federal Reserve's 2 percent core PCE target does not represent a threshold the Committee tries to hit each month; instead, it represents the inflation rate the Fed judges to be consistent with price stability over the longer run, accounting for the lags in how monetary policy affects the economy. When core PCE rises above 2 percent, the Fed typically tightens policy by raising interest rates; when it falls below, the Fed may ease. Because the Committee has committed to targeting core PCE—not core CPI—the specific PCE reading shapes every major monetary policy decision.

The gap between the two measures means the same economic conditions can look like either moderate inflation or stubborn inflation depending on which index is being watched. If core CPI rises to 3.2 percent while core PCE is at 2.8 percent, a PCE-focused Fed can communicate that inflation is closer to its target, whereas a CPI-focused Fed would see a larger and more persistent problem. This distinction is not technical; it determines whether the Fed pauses rate increases, continues them, or moves toward rate cuts—decisions that ripple through stock and bond markets.

Current inflation readings and their Fed implications

In August 2026, core PCE rose 3.0 percent year-over-year and 0.2 percent month-over-month, according to the Bureau of Economic Analysis's Personal Income and Outlays report released September 30, 2026. Headline PCE, including food and energy, came in at 3.4 percent annually and 0.3 percent monthly. These readings remain well above the Fed's 2 percent core PCE target, indicating that underlying inflation pressures persist even as the Committee weighs labor market conditions and economic growth risks against the need to control price increases.

The Fed's choice of PCE as its reference point means this single methodological decision channels billions of dollars into or out of markets whenever new inflation data is released. Investors, policymakers, and businesses rely on core PCE to understand whether the Fed will tighten, pause, or ease monetary policy. The gap between PCE and CPI reminds markets that inflation measurement is not a neutral technical exercise, but a consequential choice that shapes how the Federal Reserve interprets economic conditions and acts on them.