However, this year both DWP and Welsh Government have published a more limited range of data on Households Below Average Income, with additional cautions.
Fodd bynnag, eleni mae'r Adran Gwaith a Phensiynau a Llywodraeth Cymru wedi cyhoeddi ystod fwy cyfyngedig o ddata ar Gartrefi Islaw'r Incwm Cyfartalog, gyda rhybuddion ychwanegol.