There are many factors that may be contributing to the changing ethnic composition of Wales, such as differing patterns of ageing, fertility, mortality, and migration.
Mae llawer o ffactorau a allai fod yn cyfrannu at y newid yng nghyfansoddiad ethnig Cymru, megis gwahanol batrymau o heneiddio, ffrwythlondeb, marwolaethau, a mudo.