The Economy of Wales. In 2004, accoring to ONS provisional data, headline gross value added (GVA) in Wales was £39,243m, making the Welsh economy the tenth largest of the UK's twelve 'regions' (counting Wales, Scotland and Northern Ireland alongside the nine English Government Office Regions). It is also ranks as the 43rd largest economy in the world. The modern Welsh economy is dominated by the service sector. In 2000, services contributed 66% to GVA. The manufacturing sector contributed 32%, whilst agriculture, forestry and fishing contributed 1.5%.