They don't seem to link their sources (that's bad) but the general numbers seem to match The European Automobile Manufacturers’ Association (ACEA) report for H1 2026 [0]. They include EU + EFTA + UK.

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  0: https://www.acea.auto/pc-registrations/new-car-registrations-5-7-in-h1-2026-battery-electric-20-7-market-share/

Vehicle registrations.

I'm not entirely sure why you're getting downvoted. I wasn't able to find a source for the data but it is probably new vehicle registrations. Europe here seems to include Norway, Sweden, Finland, Iceland, Switzerland.