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.
Polish census of 1931
This situation created a difficulty in establishing the true number of ethnic non-Polish citizens of Poland. Some authors used the language criterion to attempt to establish the actual number of minorities, which was difficult considering that over 707,000 people in Polesia declared that they spoke "local" rather than any other language. Other authors used approximation based on both language and declared religion. After World War II in Soviet bloc countries the interpretation of the census was used for political purposes, to underline the officially-supported thesis that pre-war Poland incorporated areas where the non-Polish population made up the majority of inhabitants. For this purpose some authors combined all non-Polish speakers in South-Eastern Poland (namely Ukrainians, Belarusians, Rusyns, Hutsuls, Lemkos, Boykos and Poleszuks) into one category of "Ruthenians"). In fact, the census had counted speakers of Belarusian, Ukrainian, Russian, and Ruthenian languages as separate categories According to Piotr Eberhardt "it is commonly agreed that the criterion of declared language led to an overestimation of the number of Poles" in the 1931 census, he noted that " Members of minority groups believe that the language criterion led to an overestimation of the number of Poles by about one million" Eberhardt believes that criterion of religion tended to be a better indication nationality, he pointed out that 381,000 Jews identified by religion were considered Poles according to the language spoken