Until 2001 data concerning dwelling stocks by type of ownership were presented on the basis of survey (SG-01 part 3). For 2002-2007 data compiled on the basis of the balance of dwelling stocks. For 2009 - on the basis of current survey, from 2013 on the basis of modified periodic survey - M-01. Data for dwellings owned by companies are presented including State Treasury dwellings for the years between 2002-2007. From 2009 data for dwellings by type of ownership are compiled on the basis of periodic survey conducted every two years at the level of powiat. From 2013 only dwellings owned by gminas are compiled at the level of gmina, including from 2009 dwellings managed by Education and Culture entities, units performing health care activities, Social Assistance Centres. For the years 2002-2007 data concerning dwellings owned by natural persons are compiled on the basis of the balance of dwelling stocks at the level of gmina. From 2009 data were compiled on basis of the balance of dwelling stocks and current periodic survey at the level of powiats. Dwellings in buildings covered by condominiums must not be added up with other dwellings. This group concern dwellings owned by natural persons covered by condominiums as well as dwellings in buildings constituting the property or the joint property i.e. covered by condominiums. It concerns dwellings on the basis of which the condominiums were set up (dwellings of gmina, housing cooperatives, companies, State Treasury etc.).