[Note 3] The questions in the 2017-18 National Survey for Wales on Active Travel differ to previous questions and therefore data are not directly comparable with previous statistical bulletins.
[Nodyn 3] Mae'r cwestiynau yn Arolwg Cenedlaethol Cymru 2017-18 ar Deithio Llesol yn wahanol i gwestiynau blaenorol ac felly nid oes modd cymharu'r data'n uniongyrchol â bwletinau ystadegol blaenorol.