After considering all exclusions, the survey participants were selected from a population of approximately 33,000 reporting units with activity in Wales and employment of three or more people.
Ar ôl ystyried yr holl eithriadau, dewiswyd cyfranogwyr yr arolwg o boblogaeth o tua 33,000 o unedau adrodd gyda gweithgarwch yng Nghymru a chyflogaeth o dri neu fwy o bobl.