Performance against the four and twelve hour targets both improved slightly compared with April, though they were the sixth and third lowest on record respectively.
Roedd perfformiad o ran y targedau pedair awr a deuddeg awr ill dau wedi gwella rhywfaint o’i gymharu â mis Ebrill, er mai’r rhain oedd y chweched a’r trydydd isaf ar gofnod yn y drefn honno.