
Shoppers and visitors out on Oxford Street on 4th May 2025 in London, United Kingdom.
Mike Kemp | In Pictures | Getty Images
A car tax data calculation error caused the U.K.’s inflation rate to be overstated by 0.1 percentage points for the year to April, the Office for National Statistics (ONS) said on Thursday.
The ONS had initially said last month that the U.K.’s annual rate hit 3.5% in April, coming in above analyst expectations. On Thursday, the statistics body released revised data, showing the country’s consumer price index rose instead by a lower 3.4% in the 12 months to April.
The revised April figure still exceeds the 3.3% levels previously expected by Reuters analysts.
The ONS released a statement noting that an error had been identified in the Vehicle Excise Duty (VED) data provided to the statistics body by the U.K.’s Department for Transport, which is one metric used to calculate consumer prices inflation.
“The incorrect data overstates the number of vehicles subject to Vehicle Excise Duty (VED) rates applicable in the first year of registration,” it said.
This had the effect of overstating the headline CPI and Retail Prices Index (RPI) annual rates by 0.1 percentage points for the year to April 2025 only. No other periods are affected, the ONS said.
“In line with our consumer prices revisions policy, these statistics will not be amended. However, we are reviewing our quality assurance processes for external data sources in light of this issue.”
The mistake is an unwelcome smear on the already stained record of the ONS, which has been criticized in some quarters for the accuracy and reliability of its data.
The statistics agency apologized for the error and said it would be using the correctly weighted data from May 2025’s figures onward, “meaning no further statistics will be affected.”
CNBC has requested further comment from the ONS and is awaiting a response.