How to Read the CPI Inflation Report
Once a month, one government release can move stocks, gold and bond yields within seconds. Here is what the Consumer Price Index measures and which numbers traders look at first.
Key takeaways
- The Bureau of Labor Statistics publishes the CPI monthly, at 8:30 a.m. Eastern.
- Headline CPI includes everything. Core CPI excludes food and energy, which swing the most.
- Markets react to the gap between the actual number and the forecast, not to the number itself.
- Shelter is the biggest single category, about a third of the index.
What CPI measures
The Consumer Price Index tracks the average change in prices that urban consumers pay for a basket of goods and services: food, housing, gasoline, clothing, medical care, cars, airline fares and more. The headline series most people quote is the CPI-U, for all urban consumers.
Each category has a weight based on how much households spend on it. Shelter, which includes rent and an estimate of what homeowners would pay to rent their own home, is the largest. That is why rents can keep inflation elevated long after other prices cool.
The four numbers to read first
| Number | What it tells you |
|---|---|
| Headline CPI, month over month | This month's price change, everything included |
| Headline CPI, year over year | The figure usually quoted in news headlines |
| Core CPI, month over month | Underlying trend without food and energy. Watched most closely |
| Core CPI, year over year | The slower-moving trend in underlying inflation |
Monthly changes are small numbers, often 0.1% to 0.4%. A difference of just 0.1 percentage point from forecasts can move markets, because it changes expectations for Federal Reserve policy.
Why energy makes headline CPI jumpy
Gasoline and other energy prices feed into CPI quickly. When oil supply is disrupted, headline inflation can jump in a single month while core barely moves. That is why the Fed and most economists focus on core to judge the trend.
How markets react
- Hotter than expected: traders expect the Fed to keep rates higher for longer. Treasury yields and the dollar tend to rise; stocks and gold often fall.
- Cooler than expected: rate-cut hopes grow. Yields and the dollar often fall; stocks and gold tend to rally.
The first move can reverse within the hour as traders read the details. Read How Federal Reserve Decisions Affect Gold for the rate link.
CPI vs. PCE
The Federal Reserve's official 2% inflation target uses a different gauge, the Personal Consumption Expenditures (PCE) price index, published later in the month by the Bureau of Economic Analysis. PCE covers a wider range of spending and gives shelter a smaller weight, so it usually runs a bit below CPI. Markets still react more to CPI because it comes out first.
Where to find it
Release dates are on our economic calendar, and the full report, with tables by category, is on the BLS website. To see what inflation does to your own savings, try the inflation calculator.
This article is general education, not personalized financial advice. Read our editorial policy and disclaimer.
