The States-Provincial (in Dutch: Provinciale Staten, abbreviated PS – commonly known as simply the Staten) is the provincial parliament and legislative assembly in each of the provinces of the Netherlands. It is elected for each province simultaneously once every four years and has the responsibility for matters of sub-national or regional importance. Each States-Provincial is directly elected by the electors within the relevant province, and the number of seats in each States-Provincial is proportional to its population. The last provincial elections were held 18 March 2015.