Measures of inflation are some of the most popular data series on FRED. Two of the most important ones are the consumer price index (CPI), constructed by the Bureau of Labor Statistics (BLS) in the Department of Labor, and the personal consumption expenditures price index (PCE), constructed by the Bureau of Economic Analysis (BEA) in the Department of Commerce.

The CPI is probably the most widely watched measure of inflation and is used for many purposes, such as indexing Social Security payments. The Federal Open Market Committee (FOMC) has been looking at the PCE price index since the 1990s, however, and made that index the measure for its official inflation target in January 2012, when they introduced an official target.

To understand how the CPI and PCE inflation rates differ, consider a stylized representation of a price index for the year 2023 as the weighted sum of the prices of three types of goods, which we will call goods 1, 2, and 3.

P₂₀₂₃=w_1,2023 p_1,2023+w_2,2023 p_2,2023+w_3,2023 p_3,2023

The weights, w, represent how much money is spent on each good in the consumption basket. For example, gasoline would get a higher weight in a consumer price index than shoelaces. As relative prices, technology, or people’s tastes change, the weights in the baskets change.

Both the CPI and PCE are constructed in this general way, as the weighted averages of prices of various goods, but they differ.

1. The two price indices measure somewhat different baskets of goods: The CPI is designed to measure the cost of living for an urban consumer, while the PCE measures a broader cost of living. Because of this difference in emphasis, the weights in the baskets differ and the CPI famously places more emphasis on the cost of housing.
2. The weights in the CPI basket aren’t revised as often as those in the PCE basket, meaning that the PCE probably better measures consumer responses to rapidly changing relative prices.

The FRED graph above shows that monthly CPI (blue line) and PCE (red line) inflation move closely together, but the CPI generally exceeds the PCE. Over the full sample since 1960, the arithmetic average of 12-month CPI inflation was 3.77% and the standard deviation—a measure of volatility— of that series was 2.83%. The analogous figures for the PCE price index inflation were 3.31% and 2.43%. That is, the CPI inflation rate was 0.46% higher on average and somewhat more volatile. The fact that the PCE weights are revised more often than the CPI weights helps explain the higher average CPI inflation because consumers tend to substitute away from products whose prices rise sharply and the PCE index more quickly reflects such behavior.

The purple line on the FRED graph shows the difference between the CPI and PCE inflation rates, with an average value of 0.46%. This difference is almost always positive but small, usually in the range of 0 to 1%, but it does increase with overall inflation rates.

One component that may also help depict the difference between these two price indexes is annual inflation in “imputed rental of owner-occupied housing.” Shown by the green line, this is basically what a homeowner would have to pay to live in the house if they were renting it. Since CPI has higher weights for housing, this imputed rent should contribute much more to the CPI than the PCE. And it does seem to be correlated with the overall difference between the CPI and PCE inflation rates (purple line), but saying any more would require more careful analysis.

How this graph was created: On FRED, search for and select “CPI.” From the “Edit Graph” panel, change “Units” from “Index” to “Percent Change from Year Ago.” With the “Add line” option, search for “PCE” and select “Personal Consumption Expenditures: Chain-type Price Index,” then click “Add data series.” Repeat for “imputed rent,” selecting “Imputed rental of owner-occupied housing.” Add a line again, with the CPI and PCE series and apply formula a-b. Toward the top of the editing box, select “Percent Change from Year Ago” in the “Units” box and select “Copy to all.” Adjust the sample period to start on 1960-01-01.

Suggested by Christopher Neely.

FRED aggregates data from various sources. Those sources routinely revise and update the data they produce. After all, more-accurate data allow for better decisionmaking. These sources also update the names of their data series to accurately describe the activity they record. FRED incorporates these updates with an automated process.

One source, the Bureau of Labor Statistics, provides the consumer price index (CPI) dataset, which measures the average change over time in the prices paid by urban consumers. The FRED graph above displays one CPI data series that had its name changed as of February 14, 2023: from “Cable and satellite television service” to “Cable, satellite, and live streaming television service.”

This update to the series name reflects the addition of customizable internet-based live streaming of television services, which had been commonly provided via land cable and satellite wireless signals.

So what does this FRED graph show? The time period is January 1992 to December 2022, the units are percent change from a year ago, and the values are the year-over-year inflation rate of television service prices. These prices had some cyclical ups and downs but were trending downward until 2011, when that declining trend reversed. In fact, price growth for television services has markedly outpaced total price growth for its parent category, recreation services.

Stay tuned to the FRED Blog for more news of updates to additional data series names.

How this graph was created: Search FRED for “Cable, satellite, and live streaming television service.” Next, click the “Edit Graph” button, select the “Line 1” tab, and use the “Units” dropdown menu to select “Percent Change from Year Ago.” Last, select the “Format” tab to change the graph type to “Bar.”

Suggested by Diego Mendez-Carbajo.

There’s no doubt that consumer price inflation is relatively high. The consumer price index (CPI), though, is a composite of the prices of many goods and services. Thus, some show even higher inflation, such as energy and transportation, and others show lower inflation. This is what the FRED graph above is all about.

The blue bar shows overall CPI inflation. The other bars display specific categories with lower-than-average inflation. For example, both education and health services, which have had noteworthy price increases in the past, are showing much more restraint now. There are also puzzles, like alcoholic beverages, toys, and communications (for example, computers). Prices that are administratively set, such as water and trash collection, are fairly stable.

And then there’s a surprise: rents. The rent category in the CPI increases less than the overall CPI, but the news media have been referring to large rent increases for some time. Why the difference?

The reason is that the news media and the CPI consider different pools of rents. The news media mostly refer to rents that new renters face. The CPI has a rent pool that includes mostly continuing renters, whose rents are more stable or haven’t increased yet. In addition, the CPI’s rents survey samples participants every six months, precisely because rents are usually so stable. If rents have increased, there can be a delay in that increase showing up in the rents component of the CPI.

How this graph was created: Start from the CPI release table: Check the series to display, click “Add to Graph,” and shorten the sample period to the last two observations. From the “Edit Graph” panel, use the “Format” tab to choose the bar graph option.

Suggested by Christian Zimmermann.