Most of the population lives in rural villages where houses are made of stone or mud bricks, with thatched roofs and raised eaves. Bamboo and reed huts are also prevalent. Most houses have two stories, but some contain only two rooms, a sleeping room and a room for cooking. The well-constructed houses of the Sherpas are generally built of stone and timber, roofed with wooden slats. About four out of five urban dwellings in Nepal are owner occupied. The latest available figures for 1980–88 show a total housing stock of 3.1 million units with 5.6 people per dwelling. Housing shortages in urban areas have resulted in an increase of squatter villages, or slum areas.