The prescription data for these charts is based on the location of the community pharmacy where items were dispensed, rather than by the location of the general practice which issued the prescription.
Mae'r data am bresgripsiynau yn y siartiau hyn yn seiliedig ar leoliad y fferyllfa gymunedol lle cafodd eitemau eu dosbarthu, yn hytrach na lleoliad y practis meddyg teulu a roddodd y presgripsiwn.