The key differences from a Welsh Government perspective were in data collection methodology and frequency, data validation, new attendance codes and changes to an existing attendance code.
Roedd y gwahaniaethau allweddol o safbwynt Llywodraeth Cymru mewn methodoleg casglu data ac amlder, dilysu data, codau presenoldeb newydd a newidiadau i god presenoldeb presennol.