What is CPI?
CPI is the Consumer Price Index, a widely watched measure of inflation in goods and services bought by households.
The short version
CPI tracks changes in prices paid by consumers for a basket of goods and services. Markets watch it because inflation affects wages, interest rates, central-bank policy, bonds, stocks, and crypto risk appetite.
Headline vs. core
Headline CPI includes food and energy. Core CPI excludes food and energy because they can be volatile. Both matter, but core is often watched for underlying inflation trends.
Monthly vs. yearly
Month-over-month CPI shows the latest change. Year-over-year CPI compares prices with the same month a year earlier. Markets often react to the monthly number because it can reveal turning points sooner.
Why markets care
Hotter inflation can push rate expectations higher and pressure risk assets. Cooler inflation can support rate-cut expectations, lower yields, and improve risk appetite, depending on growth conditions.
What to check
Look beyond the headline: shelter, services inflation, goods prices, energy, food, wage pressure, and whether revisions change the trend.