All persons entered in the municipal population registers (the 'de jure' population). Essentially, all persons residing in the Netherlands for an indefinite period of time are entered in the population register of the municipality where they usually spend the night. People without a fixed abode belonging to the 'de jure' population are entered into the population register of The Hague.
 

Persons are considered to have a foreign background if at least one parent was born abroad. A distinction is made between persons born abroad (first generation) and persons born in the Netherlands (second generation). The foreign background is determined by the country of birth of the person (first generation) or the country of birth of the mother (second generation). If the mother was born in the Netherlands, the person is classified according to the father's country of birth.