The source for these statistics is the Understanding Society Survey; this is different to the Households Below Average Income report which uses the Family Resources Survey.
Ffynhonnell yr ystadegau hyn yw’r Arolwg Deall Cymdeithas, mae hyn yn wahanol i adroddiad Cartrefi islaw'r incwm cyfartalog sy'n defnyddio’r Arolwg o Adnoddau Teulu.