The data in this report are provisional estimates for October 2022 to September 2023 and will be revised routinely over the next 18 months to account for late returns.
Amcangyfrifon dros dro yw'r data yn yr adroddiad hwn ar gyfer Hydref 2022 i Medi 2023 a chânt eu diwygio fel mater o drefn dros y 18 mis nesaf i gyfrif am ffurflenni hwyr.