An important question pertaining to enumeration that always arises at a Population Census is whether the population should be counted on a de-facto basis i.e. at the place where a person is actually found on the reference date of the census or on a de-jure basis i.e., count a person only according to the place of normal residence.
- Of these, the enumeration on de-jure basis is more difficult to achieve without the risks of omission or double count. Enumeration of de-facto population though may appear simple will be difficult unless the movement of population is restricted on the census day and the entire enumeration is got through on a single night which is operationally difficult specifically when large population has to be covered by canvasser method.
- In practice, therefore, enumeration on a 100 per cent de-facto or de-jure basis is impossible and often times a variation or even a combination of the two is resorted to. The census instructions should clearly lay down who are the persons who should be enumerated during the census enumeration period.