Unauthorised absenteeism increased by 0.2 percentage points over 2017/18, but if you compare it with 2007/08, over nine years it has decreased by 0.2 percentage points.
Cynyddodd absenoldeb heb awdurdod 0.2% ers y flwyddyn blaenorol, ond o gymharu gyda 2007/08 mae wedi gostwng 0.2 pwynt canran dros y naw mlynedd.