The National Survey for Wales 2020-21 was adapted due to the pandemic, with a change in the mode of the survey and changes to some questions compared with previous years.
Cafodd Arolwg Cenedlaethol Cymru 2020-21 ei addasu oherwydd y pandemig, gyda newid ym modd yr arolwg a newidiadau i rai cwestiynau o’i gymharu â blynyddoedd blaenorol.