However, due to errors in in the original data from the Office of Rail Regulation (ORR) the statistics were revised by ORR on 10 May 2020.
Fodd bynnag, oherwydd gwallau yn y data oddi wrth Swyddfa Rheoleiddio’r Rheilffyrdd (ORR) cafodd yr ystadegau eu diwygio gan yr ORR ar 10 Mai 2020.