Dwellings: which construction was started, for which permits have been granted or which have been registered with a construction project and dwellings completed according to definitions valid to December 31, 2017. Data on dwellings completed and useful floor area of dwellings completed are preliminary and may change after compiling of next quarterly reports. Data on dwellings for which permits have been granted are preliminary. Since July 2015, dwellings for which permits have been granted are presented together with dwellings which have been registered with a construction project. Private construction - housing construction realised by natural persons, foundations, churches and religious associations, designated for the use of the investor or for sale or rent. Cooperative construction - housing construction realised by housing cooperatives, designated for persons being members of these cooperatives; if all dwellings in a building are constructed for sale or rent for people who are not members of a cooperative, such dwellings should be included into construction designated for sale or rent. Company construction - housing construction realized by companies of the public or private sector (excluding construction of natural persons conducting economic activity, included in private construction), designated for meeting the residential needs of the employees of these companies. Municipal construction - housing construction primarily with a social or intervention character, realised entirely with gmina funds for the residential needs of low income households. Public building society - housing construction realised by public building societies (operating on a non-profit basis) utilizing credit from the state bank BGK; dwellings realised by public building societies in order to achieve a profit designated in full for building rental housing should be included into construction designated for sale or rent. Construction designated for sale or rent - realized in order to achieve a profit by various investors (e.g., development companies, gminas), excluding construction of natural persons conducting economic activity, included in private construction. This form of construction also includes construction of public building societies, realized in order to earn a profit (from rent or the commercial sale of dwellings), designated in full for building rental housing.