In August 2009, the Bureau of Labor Statistics (BLS) restructured the text of the CPI news release to focus on the price movements of three broad expenditure categories, namely Food, Energy, and All items less food and energy. Table A within the CPI news release text was also updated in August 2009 to reflect this new structure. Before August 2009, the text of the CPI news release had focused on eight CPI 'major groups' (Food and beverages; Housing; Apparel; Transportation; Medical care; Recreation; Education and communication; and Other goods and services).
While the text of the CPI news release was restructured in 2009, seven additional CPI news release tables continued to be published using the eight major groups. BLS is redesigning these news release tables, to reflect the focus on Food, Energy, and All items less food and energy. Within these three broad categories, CPI item series will be further divided into commodities and services.
A mock-up of the new CPI news release tables can be found at http://beta.bls.gov/cpi/redesigned_cpi_tables/cpiprmockup.htm. Comments or questions about these new tables can be forwarded to cpi_info@bls.gov. The public comment period runs through October 31, 2011.
Beyond the redesign in the structure of the CPI news release tables, several other improvements to these tables have been made.
The new Table 1 gives a summary of the index series which typically contribute to changes in the Consumer Price Index for All Urban Consumers (CPI-U).
The new Table 2 will show the full publication stub using the new structure for the CPI-U, including 11 new items series that were created to augment the redesign in the publication structure.
Table 3 will show aggregate item series (e.g., Transportation) that do not fall under the Food, Energy, and All items less food and energy structure.
Table 4 will show the All items indexes at the local, regional, and city-size class levels. Table 5 will show the Chained Consumer Price Index for All Urban Consumers (C-CPI-U), and presents a history of annual percentage changes in the C-CPI-U compared to the CPI-U.
Table 6 will focus on 1-month seasonally adjusted changes in the CPI-U, while table 7 will focus on 12-month not seasonally adjusted changes. Tables 6 and 7 will present three additional pieces of data to help users better interpret index changes. First, these tables will show the effect each item has on the price change for All items. For example, if the effect of food is 0.4, and the index for All items increased 1.2 percent, it can be said that increases in food prices accounted for 0.4 / 1.2, or 33.3 percent, of the increase in overall prices for that period. Said another way, had food prices been unchanged, the All items index only would have increased 0.8 percent (or 1.2 percent for All items, minus the 0.4 effect for Food). Effects can be negative as well. For example, if the effect of food was a negative 0.1, and the All items index rose 0.5 percent, the All items index actually would have been 0.1 percent higher (or 0.6 percent) had food prices been unchanged.
Second, standard errors for percent changes will be shown on tables 6 and 7. Confidence intervals for statistics can be created using standard errors; e.g., roughly 95% confidence intervals can be constructed using two standard errors. For example, if an item increased 3.7 percent, and its standard error was 0.6 percent, the 95% confidence interval for that price change can be said to be 3.7 percent plus or minus two standard errors, or 3.7 percent plus or minus 1.2 percent.
Finally, each item series in tables 6 and 7 will show the last time that item had a price change as large (or as small) as the percent change published that period. For example, if bananas rose 3.7 percent, and that was its largest increase since November 2007, that would be noted in the new tables.
In addition, most of the existing tables show the relative importance, or weight, of each item category as of the previous December. The relative importance columns in the new tables will be improved in that they will be updated monthly to reflect the change in relative prices over time.
Finally, there will no longer be any news release tables that focus on the Consumer Price Index for Urban Wage Earners and Clerical Workers (CPI-W). That said, the CPI-W All items index level and percent changes will still be noted in the text of the news release.
Last Modified Date: October 5, 2011
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