There was a gradual fall between November 2020 and March 2021, however the number has since increased and reached the highest level on record in August 2021.
Roedd gostyngiad graddol rhwng mis Tachwedd 2020 a mis Mawrth 2021, ond mae’r nifer wedi cynyddu ers hynny, ac wedi cyrraedd y lefel uchaf erioed ym mis Awst 2021.