2.4. Notes regarding estimates of Palestinian refugees and IDPs (see Table 2.1) 2.4.1. UNRWA Registered 1948 Refugees UNRWA reported 5,807,653 registered refugees as of 31 December 2021; these figures are based on data voluntarily supplied by those registered refugees. UNRWA registration statistics do not claim to be, and should not be, taken as statistically sound or comprehensive demographic data. This information is collected by UNRWA for its own internal management purposes, and to facilitate certification of refugee eligibility to receive education, health, and relief and social services. New information on births, marriages, deaths, and changes in place of residence is recorded only when a refugee requests the updating of the family registration card issued by the Agency. UNRWA does not carry out a census, house-to-house survey, or any other means of verifying place of residence or other statistical data. Refugees will normally report births, deaths, and marriages when they seek a service from the Agency. Births, for instance, are reported if the family makes use of UNRWA maternity and child health services, or when the child reaches school age if admission is sought to an UNRWA school, or even later if neither of these services are needed. Deaths tend to remain under-reported. While families are encouraged to have a separate registration card for each nuclear family (parents and children), this is not obligatory. Information on family size may therefore include a mix of nuclear and extended families, and in some cases may include as many as four generations. 2.4.2. Non-registered 1948 Refugees The calculation of 1,220,018 persons as 1948 non-registered refugees at end of 2021 is based on the assumption that, “UNRWA registered refugees represent approximately three-quarters of Palestinian refugees worldwide.”306 This assumption was applied to the calculation for the three regions: Syria, Lebanon and Jordan. As for the oPt, the results of the 2007 PCBS censuses revealed that non-registered 1948 refugees represent 1.43 percent of the total Palestinian population in the oPt. With regards to the growth rate, it was 2.86 percent for 2007, 2.87 percent for 2008, 2.88 percent for the years 2009-2014, 2.9 percent for 2015-2016, 2.5 percent for 2017-2020, and 2.4 percent in 2021. 307 Alternative estimates: Based on The Palestinian Nakba 1948: The Register of Depopulated Localities in Palestine, London, issued by the Palestinian Return Center in 1998, non-registered refugees compose roughly 27.1 percent of registered refugees.308 This would result in a total of 1,573,850, which is higher than the above estimated figure. 306 UNRWA, ‘Refugee Statistics 1953-2000’ (Palestine Remembered, 2000) <http://www.palestineremembered.com/ download/RefugeesStats.pdf> accessed 3 October 2022. 307 PCBS, Statistical Yearbook 2021 (n 216). 308 Salman Abu Sitta, The Palestinian Nakba 1948: The Register of Depopulated Localities in Palestine (Palestinian Return Centre (PRC) 1998). 64