Mae’r gwahaniaethau mawr rhwng canlyniadau’r cyfrifiad a’r arolygon yn ei gwneud hi’n heriol i ddefnyddio’r ystadegau hyn i hysbysu polisi iaith. Felly, rwyf yn cyhoeddi’r datganiad hwn heddiw er mwyn eich hysbysu o’r gwaith rydym yn ei wneud i wella cydlynu rhwng gwahanol ffynonellau am ystadegau ar y Gymraeg yng Nghymru. Mae ystadegwyr Llywodraeth Cymru wedi cyhoeddicynllun gwaithar y cyd â’r Swyddfa Ystadegau Gwladol (ONS) i archwilio’r gwahaniaethau rhwng y ffynonellau data hyn yn fanylach.
The large differences between the census and survey results make it challenging to use these statistics to inform Welsh language policy. I am therefore publishing this statement today to inform you of the work we are undertaking to improve the coherence of different sources relating to Welsh language statistics in Wales. Welsh Government statisticians have published a jointwork planwith the Office for National Statistics (ONS) to examine the differences between these data sources in greater detail.