Malaysia is a federal constitutional elective monarchy; the only federal country in Southeast Asia. The system of government is closely modelled on the Westminster parliamentary system, a legacy of British rule. The head of state is the King, whose official title is the Yang di-Pertuan Agong. The King is elected to a five-year term by and from among the nine hereditary rulers of the Malay states. The other four states, which have titular Governors, do not participate in the selection. By informal agreement the position is rotated among the nine, and has been held by Abdullah of Pahang since 31 January 2019. The King's role has been largely ceremonial since changes to the constitution in 1994, picking ministers and members of the upper house.