Palestinian Central Bureau of Statistics (PCBS) website – http://www.pcbs.org/phc_97/phc_covr.aspx
… For the first ever Palestinian census, the de-facto approach was adopted with some exceptions. The census count included the following categories:
A : The Categories underwent complete data collection.
1.All persons present in the Palestinian territories on the census reference date, irrespective of nationality, purpose of stay and place of residence in the Palestinian territories.
2.All temporarily living abroad (for one year prior to the night of the reference date) and who have a usual place of residence in the Palestinian territories. Those persons are enumerated as parts of their households.
3.All Palestinians studying abroad irrespective of the study period and the period of stay abroad along with all Palestinian detainees in the Israeli jails regardless of the detention period.
B : Palestinian abroad: Categories underwent data collection on their numbers and sex only This category includes Palestinians who live abroad for more than one year and who have a usual place of residence in the Palestinian territories and have identity cards (except for students and detainees enumerated in the previous category) irrespective of the purpose of stay abroad.
Hassan Abu Libdah, former Head, PCBS, News Conference, El Bireh, February 26, 1998: “We counted 325,000 people living outside of the Palestinian lands for more than one year, who carry Palestinian ID cards and can return at any time. This number is a minimum, and is not precise because we could not contact all the families living abroad.”
According to the Palestinian Election Commission (Oct. 2004), the population count included 200,000 18-year-old and older who were overseas for over a year. In 2004/05 the median Palestinian age was 18, which means that about 400,000 Palestinians, who were abroad for over a year, were included in the population count.
Louie Shabanah, former Head, PCBS, “Ne’eman Inst.”, Haifa Technion (June 8, 2005): “Our Health Ministry accounts for less births, because – unlike the PCBS – it excludes overseas births….”