The Philippines is governed as a unitary state, with the exception of the Bangsamoro Autonomous Region in Muslim Mindanao (BARMM), although there have been several steps towards decentralization within the unitary framework. A 1991 law devolved some powers to local governments. The country is divided into 17 regions, 81 provinces, 146 cities, 1,488 municipalities, and 42,036 barangays. Regions other than Bangsamoro serve primarily to organize the provinces of the country for administrative convenience. , Calabarzon was the most populated region while the National Capital Region (NCR) the most densely populated.