In these countries, migratory flows usually begin with internal displacements which, depending on the intensity and the duration of conflict, become frequent and may lead to large international out-migration. Therefore, it adopts a broader indicator of economic and social development. The majority of the "transitioning countries" in this typology fall into the OECD category of "high and sustained growth," while some from that category of OECD have graduated to "aspirational" and others are still in the "development momentum" category.