In 2021, among people aged 20 years or older, 20 to 44 year olds was the age group most likely to be able to speak Welsh (16.5%).
Yn 2021, ymhlith pobl 20 oed neu'n hŷn, pobl 20 i 44 oed oedd y grŵp oedran mwyaf tebygol o siarad Cymraeg (16.5%).