25 November 2022
We have identified and corrected an error in the Office for National Statistics (ONS) Producer Price Indices (PPI) affecting data from January to October 2022.
The error was because of diesel fuel not being allocated a correct weight within the output price index, which resulted in Petroleum Products being around half the correct weight of 6.5% since the start of the year.
This error does not affect the overall trend, but it has led to the headline 12-month output price rate being revised up by an average of 1.8 percentage points between January and October 2022.
The 12-month output price rate now stands at 17.2% in October 2022. The peak was revised up to 19.7% in July 2022.
The correction in Output PPI weights, and the inclusion of diesel prices within the data, now mean that from January to October 2022 Petroleum Products has the largest positive contribution to the 12-month rate of output inflation. For October 2022, Petroleum Products contributed 6.1 percentage points to the 12-month rate (revised from 0.0). This is notably higher than the second main contributor, Food Products, which has a revised contribution of 3.5 percentage points in October.
The Input PPI weights were less affected. Although the upwardly revised Output PPI indices are used to estimate domestic inputs, the effect of the higher price was offset by a lower contribution from imported fuels, which was already reflected in diesel prices. The average impact on the input 12-month rate was 0.1 percentage points. In October 2022, the 12-month input price rate stood at 19.5%, with the peak in June 2022 now standing at 24.5%.
This issue occurred because of a processing error. All the affected datasets from January to October 2022 have been corrected. However, the commentary within the statistical bulletins has not been amended. Users should therefore refer to the datasets for the corrected figures. We are adopting additional system checks to ensure that this does not happen in the future. We apologise for any inconvenience this may have caused.
09 December 2022
Last month we advised users of a weighting error for diesel fuel within the ONS Producer Price Indices (PPI). While most tables were updated correctly, some indices in datasets 2 (MM22) and 8 (PPI reference table) were not but have now been updated today.
Subsequent quality assurance checks have identified a further issue with some detailed item prices feeding into incorrect groups within the food section of the PPI basket.
As a result, the ONS will not be publishing next week’s PPI bulletin and data for November 2022, while further investigations are undertaken.
While this is being completed, we advise caution using the PPI datasets which may be subject to revision.
We will keep users updated on our progress and will provide a further update in January 2023. We apologise for any inconvenience caused.