.HEADLINES concerning rising cost of living in United States usually pertain to the nation's consumer-price index (CPI), the most commonly used procedure of transforming prices. CPI inflation decreased in August to 2.5% year-on-year. But when United States's main financiers fulfill on September 17th to talk about reducing interest rates, they will concentrate on a different mark. Considering that 2000 the Federal Get has made use of the personal-consumption-expenditures (PCE) consumer price index, instead the than CPI, as its recommended step of inflation. It is against this that the Fed's target for inflation, 2%, is contrasted. What are the differences between the steps-- and why performs the Fed use the PCE?