Query: How many districts is the continental Portugal divided into?
Context: For statistical purposes the Portuguese government also identifies NUTS, inter-municipal communities and informally, the district system, used until European integration (and being phased-out by the national government).[original research?] Continental Portugal is agglomerated into 18 districts, while the archipelagos of the Azores and Madeira are governed as autonomous regions; the largest units, established since 1976, are either mainland Portugal (Portuguese: Portugal Continental) and the autonomous regions of Portugal (Azores and Madeira).