Demographics of Poland
According to GUS, about 38,325,000 people live in Poland, however, the same report states that the number of residents living in the country all the time is approximately 37,200,000; with 1,125,000 people living abroad for 6 to 7 months or more. It means that the permanent population may be correspondingly smaller.
History of Poland
The population grew steadily, reaching 35 million in 1939. However, the overall economic situation in the interwar period was one of stagnation. There was little money for investment inside Poland, and few foreigners were interested in investing there. Total industrial production barely increased between 1913 and 1939 (within the area delimited by the 1939 borders), but because of population growth (from 26.3 millions in 1919 to 34.8 millions in 1939), the "per capita" output actually decreased by 18%.