Fieldwork for the fourth year of the survey, collecting 2021 data, closed in December, and is in the process of being validated, analysed and quality checked.
Daeth gwaith maes ar gyfer pedwaredd flwyddyn yr arolwg, sef casglu data 2021, i ben ym mis Rhagfyr, ac rydym wrthi'n ei ddilysu, ei ddadansoddi a sicrhau ei ansawdd.