The responses received to the public consultations held by both the UK and Welsh Governments in 2016 to 2017 have shaped the development of the reforms.
Datblygwyd yr holiaduron a ddefnyddiwyd ar gyfer arolwg 2019 i 2020 gan Lywodraeth Cymru yn dilyn ymgynghoriad â defnyddwyr ystadegau am y Gymraeg.