International migration is a term used to refer to change of usual residence between nations. The number of international migrants is always much smaller than the total number of persons traveling across international frontiers, because the overwhelming majority of such travelers do not intend to change their usual residence. International migration is contrasted with internal migration, which refers to a change of usual residence within a nation. The term immigration is used to denote the flow of persons establishing a usual residence in a given nation whose last residence was in some other nation. The term emigration is used to denote the flow of persons relinquishing a usual residence in a given nation to establish residence in some other nation. Net international migration denotes the difference between the number of persons immigrating to a given nation in a given period and the number emigrating from that...