Skip to main content
The FRED® Blog

Posts tagged with: "PCEPILFE"

View this series on FRED

Measuring inflation trends

Why use different inflation measures for policy analysis?

Congress has instructed the Federal Reserve to pursue monetary policies that promote maximum employment and price stability. The Federal Open Market Committee (FOMC) has determined that “inflation at the rate of 2 percent, as measured by the annual change in the price index for personal consumption expenditures [PCE], is most consistent over the longer run with the Federal Reserve’s statutory mandate” for price stability. As of March 2018, the year-over-year percent change in the PCE was 2.01 percent, or just 1 basis point above the FOMC’s 2 percent target. However, inflation was substantially lower over much of the past year—as low as 1.40 percent in July 2017—and economists were uncertain whether the low readings reflected temporary factors that would soon dissipate or an underlying inflation rate that was below the level consistent with price stability.

Because the inflation rate measured by the headline PCE tends to be volatile from month to month, many observers monitor other measures, such as the PCE excluding food and energy prices (“core PCE”), to gauge underlying inflation trends. The near-term growth in core PCE is among the economic variables that the FOMC includes in its quarterly Summary of Economic Projections. As of March 2018, the year-over-year growth in core PCE was 1.88 percent. Some critics argue that this measure of inflation is “rotten,” however, because it arbitrarily excludes particular categories of goods whose prices affect the cost of living.

An alternative, and somewhat less arbitrary, measure of underlying inflation trends is based on the mean of changes in the prices of the individual goods and services that make up the price index after dropping items with exceptionally large or exceptionally small price changes in a given month. For example, the Federal Reserve Bank of Dallas calculates a trimmed mean PCE inflation measure designed to hew closely to the trend in overall PCE inflation. By omitting price changes for goods and services having the largest or smallest price movements in a given month, extreme values have less impact on the measured inflation rate, which arguably is a better measure of underlying inflation trends than the traditional core measure.

The chart plots the headline, core, and Dallas Fed trimmed mean PCE inflation rates, measured as percent changes over the past 12 months, for the past year. Whereas the headline PCE inflation rate increased from 1.73 percent in February to 2.01 percent in March, and the core rate rose from 1.57 percent to 1.88 percent, the trimmed mean rose only from 1.71 percent to 1.77 percent. Hence, in contrast with the headline and core measures, the trimmed mean indicates little, if any, change in underlying inflation pressures in recent months, suggesting that low inflation readings might be more reflective of underlying trends than temporary special factors.

How this graph was created: Search for “PCE,” check the three series, and click on “Add to Graph.” From the “Edit Graph” menu, change the units to “Percent Change from Year Ago.” Change the frequency to “Monthly” and the starting date to “2017-03-01.”

Suggested by David Wheelock.

View on FRED, series used in this post: PCEPI, PCEPILFE, PCETRIM12M159SFRBDAL

The trouble with food and energy

There are many ways to measure inflation. One popular method used for monetary policy purposes is to look at the price index for personal consumption expenditures excluding food and energy. Why exclude food and energy? Aren’t those important items that matter a great deal to households? The reason is straightforward: These price categories are considered to be excessively volatile, and including them would make it more difficult for policymakers to pin down the inflation trend. The graph above makes this point visually by comparing the PCE inflation rates with and without food and energy.

Usually when you add items to an index, you reduce the volatility of that index. This same premise is at work when you add assets to an investment portfolio—i.e., when you diversify to reduce volatility. But this does not happen when the item you add is excessively volatile. And, again, food and energy are excessively volatile. Food is subject to large price variations due to external shocks, mostly on the supply side, such as weather. Energy is subject to shocks as well: supply shocks such as discoveries, wars, political risk, and infrastructure issues and demand shocks such as climate events. This happens with food and energy much more than it does for other items included in personal consumption expenditures.

How this graph was created: Search for “PCE.” Then go to the “Filter Series by Tags” box to the left and enter “price index.” Select the first two monthly series that appear and add them to the graph. Change the units for both series to “Percent Change From Year Ago.”

Suggested by Christian Zimmermann

View on FRED, series used in this post: PCEPI, PCEPILFE

Which measures of inflation are relevant for policy?

The Federal Reserve has set a 2% inflation target. Does it meet that target? It depends on which inflation rate you consider. FRED offers many different series for the U.S. that reveal different views of inflation because they pertain to different groups of goods and services. The graph above shows eight series that receive a lot of attention in the context of policy: Three are above and five are below that 2% target. How are they different? Some look only at consumption expenses or production costs. Some include overall economic activity. Some exclude energy and food, price categories thought to be volatile and thus capable of clouding the picture of underlying inflation. (For example, removing the currently low prices of oil and its derivatives clearly leads to higher inflation numbers.) Some focus on prices that move slowly, which are thought to be good indicators of trend inflation. And one index considers only the median in the distribution of price changes. You can consider even more series in FRED. The point is that there’s a wide spread across those inflation rates, and determining which is the most relevant isn’t easy.

How this graph was created: One of the many way to graph these series is to search for “price” and restrict the choices with tags such as “nation,” “usa,” and “sa” (seasonally adjusted). These eight are likely to be at the top of these search results. Select the series you want and click the “Add to graph” button. Some series are indexes and others are inflation rates, so modify the units to show “Percentage change from year ago” for the series in index form. Finally, to add the black horizontal line at 2%, open the “Add series” panel and select “Trend series” from the pulldown menu. Once it’s added, modify it by choosing 2 for the initial and final values and change the color to black. Oh… We also removed the axis label because it became unwieldy with eight depicted series.

Suggested by Christian Zimmermann

View on FRED, series used in this post: A191RI1Q225SBEA, CPIAUCSL, CPILFESL, CRESTKCPIXSLTRM159SFRBATL, MEDCPIM158SFRBCLE, PCEPI, PCEPILFE, STICKCPIM159SFRBATL


Subscribe to the FRED newsletter


Follow us

Back to Top