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9.33. Regarding mode 4, it should also be noted that the interest might not be in the total number of trips, but in the combination of the number of persons, the number of trips taken by those persons, the duration of each trip and the total duration of travel per person. The entry/departure card could provide information on the repetition of trips only if the persons are uniquely identified by the entry/departure card and the registrations at different border crossing points are stored in the same database.
Next: C.4. Work permits
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[1] Recommendations on Statistics of International Migration, revision 1 (RSIM rev.1), Statistical Papers, Series M, No. 58/rev.1 (United Nations publication, Sales No. E.98.XVII.14). Available from https://unstats.un.org/unsd/pubs/gesgrid.asp?ID=116.
[2] See box V.2 MSITS 2010 for further discussion on the identification of the employer-employee relationship.
[3] See World Tourism Organization, Tourism as an International Traded Service: A Guide for Measuring Arrivals and Associated Expenditures of Non-residents (Madrid, 2005), on the results of a survey of country practices in the use of entry/departure cards, available from http://www.unwto.org/statistics/border.pdf.
[4] For example, the Australian Bureau of Statistics compares the actual length of stay to the expected length of stay on the entry card, which allows for calculation of a "realization ratio" so that the number of visitors expecting to stay more (or less) than a year can be adjusted at the time of arrival to allow for an estimate of those who will actually stay for the amount of time they expected.
[5] MSITS 2010 sets out the framework to define mode 4 in the context of the existing tourism and migration statistical recommendations. Statistical compilers should review that framework and, in particular, table V.3 in MSITS 2010, which presents the links between the coverage of RSIM rev.1 and that ofIRTS 2008 in terms of purpose of trip or migration and length of stay: identifying categories of interest for GATS mode 4.
[6] See Tourism as an International Traded Service”, para. 2.45.