The revised figures are between 5 and 6 percentage points lower than previously published due to an error in their calculation, and affects all health boards.
Mae'r ffigurau diwygiedig rhwng 5 a 6 phwynt canran yn is nag a gyhoeddwyd yn flaenorol oherwydd camgymeriad wrth gyfrifo, ac maent yn effeithio ar bob bwrdd iechyd.