For every international commercial airline flight arriving at or departing from a U.S. port city (except of those flights originating or terminating in Canada), the Immigration and Naturalization Service (INS) of the United States Department of Justice requires the completion of an international flight report (Form I-92). The information derived from these international flight reports is extracted, processed and summarized by the U.S. Department of Transportation. This information comprises the INS module of DBP's INTERNATIONAL database.

For departing flights, the I-92 forms are collected at the very last domestic port, or gateway city, prior to leaving the United States. The form shows how many passengers (both revenue and non-revenue passengers) and crew members are on board the flight. In other words - as you would expect given the objectives of the agency collecting the information - the count is made of the total persons on each flight. Moreover, all passengers are shown as departing from the gateway city at which the forms are completed regardless of their previous origins.

For arriving flights, the I-92 forms are collected at the port where immigration inspections are conducted. Nearly always, these inspections take place at the very first port of arrival in the U.S. However, in some rare instances, immigration inspection is deferred for those passengers traveling on the same flight to a further downline point within the United States. As is the case with departing flights, all passengers are shown as arriving at the gateway city in which the forms are completed, regardless of subsequent destination.

As previously noted, I-92 forms are not usually collected on flights between the United States and Canada. There is, in consequence, almost no U.S.-Canadian traffic flow data in the INS module. Very occasionally, however, on flights conducted between the U.S. and Canada by a third nation's air carrier, some international flight reports are filed. Though the information extracted from these sporadic reports is not purged from the INS module, it should by no means be considered as accurately reflecting U.S.-Canadian traffic flows.