The number of people reporting being able to speak Welsh decreased from December 2018 to March 2020, before generally increasing again since then.
Gostyngodd nifer y bobl sy'n adrodd eu bod yn gallu siarad Cymraeg rhwng mis Rhagfyr 2018 a mis Mawrth 2020, cyn cynyddu’n gyffredinol eto ers hynny.