In reply to Sanne Peters ️‍.

You may find it aggregated in other larger corpora, but here's a link to the most recent language census for England and Wales from 2011 which will break out further details there that you don't currently show: https://www.ons.gov.uk/peoplepopulationandcommunity/culturalidentity/language/articles/languageinenglandandwales/2013-03-04