This file is a best fit lookup between Output Areas and National Assembly for Wales constituencies (NAWC) and National Assembly for Wales electoral regions (NAWER) as at 31 December 2018 in Wales. (File Size - 2 MB) Field Names - OA11CD , NAWC18CD, NAWC18NM, NAWER18CD, NAWER18NMField Types - Text, Text, Text, Text, TextField Lengths - 9, 9, 39, 9, 19REST URL of Feature Access Service – https://services1.arcgis.com/ESMARspQHYMw9BZ9/arcgis/rest/services/OA11_NAWC18_NAWER18_WA_LU_6a7587fc5cdd4822a79d1be239ae4afd/FeatureServer
For more information and an overview of best-fitting follow this link - https://geoportal.statistics.gov.uk/datasets/f0aac7ccbfd04cda9eb03e353c613faa/about