The Census results and APS results for 2001 and 2011 have also been plotted on the chart above to indicate the large discrepancy between the two sources at the same time periods.
Mae canlyniadau’r Cyfrifiad ar gyfer 2001 a 2011 wedi’u plotio ar y siart uchod hefyd, er mwyn dangos y gwahaniaethau rhwng y Cyfrifiad a’r Arolwg Blynyddol yn yr un cyfnod.