Check out the following video, part of the Bizkaia Talent initiative and featuring Pedro Luis Uriarte (President of the Bargaining Commission of the Economic agreement from the Basque Government side in 1980), which explains succinctly the very special fiscal system that exists in Hegoalde or the Southern Basque Country.

If you are interested in this topic, check out Basque Economy from Industrialization to Globalization, by Mikel Uranga, free to download here.

See, too, The Basque Fiscal System Contrasted to Nevada and Catalonia: In the Time of Major Crises, edited by Joseba Aguirreazkuenaga and Xabier Irujo.