Forecasting responsibilities – the OBR will continue to produce all UK-wide economic and fiscal forecasts for the UK government (which includes revenues from taxes devolved in Wales.
Mae'r Swyddfa Cyfrifoldeb Cyllidebol yn cynhyrchu rhagolygon Treth Gwarediadau Tirlenwi i gyd-fynd â chyllidebau Llywodraeth Cymru a Llywodraeth y DU.