There has been concern for many years at the substantial transfers from local government in Wales to HM Treasury, via the Welsh Government, as a result of this system.
Mae'r symiau mawr sy'n cael eu trosglwyddo o lywodraeth leol Cymru i Drysorlys ei Mawrhydi drwy Lywodraeth Cymru o ganlyniad i'r system hon wedi achosi cryn bryder ers sawl blwyddyn.