摘要：The study presents the demographic development of big cities (≥100,000 inhabitants within the city’s administrative borders) in Poland from 1950 to 2016. The article demonstrates the similarities and differences in these cities’ demographic development, showing demographic trends in Poland’s various periods of socio-economic development using the graphical trajectory method. The presented study on demographic development of Polish cities uses trajectories, showing them to be an additional useful tool in analyses of demographic development of cities, regions and other territorial units. It was indicated that this simple graphic representation opens new interpretative possibilities; it demonstrates development stages, shows both the process nature (demographic development of cities in this case), and whether this process is progressive or regressive in nature. The trajectory method allows us to read the dynamics of changes in a particular process (in the distances between successive trajectory points).
