However, it is likely that due to the way the weekly data are collected and the lack of validation that there would be greater and more significant differences at below the Wales level.
Fodd bynnag, mae'n debygol, oherwydd y ffordd y mae'r data wythnosol yn cael eu casglu a'r diffyg dilysiad y byddai gwahaniaethau mwy a mwy arwyddocaol o dan lefel Cymru.