No weighting is applied to account for the different sizes of each local authority, that is because that information is not available from Google, only relative change.
Nid yw’r data yn cael eu pwysoli gan ystyried maint pob awdurdod lleol, nid yw’r wybodaeth honno ar gael gan Google, yr un beth sy’n cael ei ddangos yw’r newid cymharol.