90.3% of resident households (i.e. households headed by a Singapore citizen or permanent resident) own the homes they live in, and the average household size is 3.43 persons (which include dependants who are neither citizens nor permanent residents).[202] However, due to scarcity of land, 80.4% of resident households live in subsidised, high-rise, public housing apartments known as "HDB flats" because of the government board (Housing and Development Board) responsible for public housing in the country. Also, 75.9% of resident households live in properties that are equal to, or larger than, a four-room (i.e. three bedrooms plus one living room) HDB flat or in private housing.[202][203] Live-in foreign domestic workers are quite common in Singapore, with about 224,500 foreign domestic workers there, as of December 2013.[204]