The proportion of new cars sold in the UK which are either fully electric (BEVs) or which are plugin hybrids which can be used as though they were fully electric (PHEVs) has been rising sharply over the past few years, though this growth slowed down last year:

The source for this market will be the SMMT's figures for the year to December 2024. They publish figures every month, and it will be their December 2024 report (published in early January 2025) which has the relevant numbers:

https://www.smmt.co.uk/2024/01/new-car-market-delivers-best-year-since-2019-as-fleets-fuel-growth/

If the figures are on the cusp between two categories (eg. the rounded figures add up to exactly 25%), I will use the raw numbers published by the SMMT to see whether it is under or over the threshold.