U.S. flag

An official website of the United States government

Department of Labor Logo United States Department of Labor
Dot gov

The .gov means it's official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you're on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Producer Price Indexes
Bureau of Labor Statistics > Producer Price Indexes > About > Notices

PPI Publishes Variance Statistics for 2021

Summary of variance estimates for PPI price changes, 2021

Variance is a measure of the uncertainty caused by the use of a sample of producer prices instead of the complete universe of producer prices. The most commonly used measure of variability is the standard error of the estimate—the square root of the variance. The standard error of the percent change in the Producer Price Index (PPI) can be used to construct confidence intervals and to determine whether the percent change for a particular PPI series is significantly different from zero.

For example, the 1-month median absolute percent change for the final demand index in 2021 was 0.81 percent, and the 1-month median standard error (SE) was 0.15 percent. (See table 1 of the 2021 PPI variance data release.) Margins of error for a point estimate are commonly expressed as plus and minus two standard errors. The margin of error for the 1-month final demand index in 2021 is approximately 0.81 percent plus and minus 0.30 percent (2 x 0.15 percent). Therefore, in a typical 1-month period in 2021, the percent change in the final demand index was probably somewhere between 0.51 percent and 1.11 percent. On a 12-month basis in 2021, the median absolute percent change for the final demand index was 7.76 percent, and the median SE was 0.36 percent. Margins of error for the 12-month period can be calculated in the same way as for the 1-month period.

 

Table 1 provides variance estimates for 1-month and 12-month percent changes for the Producer Price Index Final Demand-Intermediate Demand Indexes. (XLSX) (PDF)

Table 2 provides variance estimates for selected 1-month and 12-month percent changes for the Producer Price Index commodity-based indexes. (XLSX) (PDF)

Table 3 provides variance estimates for selected 1-month and 12-month percent changes for the Producer Price Index industry-based indexes. (XLSX) (PDF)

Last Modified Date: July 25, 2022