Please see ASHE, Low Pay and Annual Survey of Hours and Earnings Pension Results Quality and Methodology Information.
Gweler Yr Arolwg Blynyddol o Oriau ac Enillion, Cyflogau isel a Gwybodaeth am Ansawdd a Methodoleg Canlyniadau Pensiwn yr Arolwg Blynyddol o Oriau ac Enillion.