Consumer Price Index (all urban consumers, all items)
The consumer price level — an index of what a fixed basket of household purchases costs. Inflation is how fast it changes, not the number itself.
What it measures
The cost of a basket of goods and services bought by urban consumers — food, housing, transport, medical care, and the rest — expressed as an index where the 1982–84 average equals 100.
How it is measured
BLS staff collect around 80,000 prices a month from stores, service providers, and landlords across urban areas; the weights come from the Consumer Expenditure Survey of what households actually buy. This series is seasonally adjusted.
Reading it over a presidential term
An index level is meaningless on its own — 320 is not “bad”. Score this one as a change from start to end of term in annualized percent, which is the inflation rate over the term. An average level over a term measures nothing but the passage of time.
What it leaves out
The basket is a national average that matches no particular household; rent and owners’ equivalent rent are measured with a lag; and the Federal Reserve targets a different index (PCE), which usually runs a little lower. Old months are not revised, but the seasonal factors are.
Which direction counts as better?
Almost everyone prefers low, steady inflation to high inflation — but falling prices bring their own damage, the right target is a live argument, and how much of a term’s inflation belongs to the President rather than to energy markets, supply chains, or the Fed is exactly the judgment this site leaves to you.
Chart this series · See it by president · Download the data · The source at FRED