Children aged 5 to 15 years old saw a 6.0 percentage point decrease in the proportion reported as being able to speak Welsh between 2011 and 2021.
Bu gostyngiad o 6.0 pwynt canran mewn plant rhwng 5 a 15 oed y nodwyd eu bod yn gallu siarad Cymraeg rhwng 2011 a 2021.