Internal to cross-border displacement A scant evidence base Just as there is insufficient data on IDPs’ progress toward durable solutions and the processes that lead to the end of displacement, there is also a lack of data and information when it comes to the scale, scope and patterns of IDPs’ flight across international borders and the factors that prompt or inhibit such onward movements.163 It is currently impossible to determine the global number or proportion of IDPs from areas or countries affected by conflict who eventually cross international borders. The available evidence, based on a small number of case studies, indicates that figures depend largely on the context. This, combined with the fact that we do not know how representative the studies are, makes it impossible to extrapolate to generate even regional estimates. IDMC’s data on internal displacement associated with conflict does point to a correlation between IDP and refugee movements: many of the countries that produce the most refugees are also home to the highest numbers of IDPs. Six of the ten countries that produced the most refugees in 2015 – Afghanistan, Colombia, DRC, Sudan, South Sudan and Syria – were also among the ten with the largest numbers of IDPs (see figure 2.1).164 A large part of Afghan and Syrian refugees, around 55 and 85 per cent respectively, interviewed in Greece in early 2016 said that they had not left directly their areas of origin, the implication being that they had formerly been IDPs, refugees in other countries or another type of migrant before arriving in Europe.165 Despite Syria’s relentless conflict, the number of IDPs dropped by more than a million from 2014 to 2015, partly the result of some crossing international borders to seek protection outside the country.166 Nearly 70 per cent of female asylum seekers from countries in Central America’s northern triangle (NTCA) were also internally displaced before making the decision to flee abroad.167 In other countries and contexts, however, this ratio can differ significantly. For example, in a survey of migrants and refugees arriving in Europe via the western Balkans between December 2015 and May 2016, 90 per cent of the interviewees Refugee children at the Depethe camp in Chios, Greece. Photo: NRC/Tiril Skarstein, April 2016 OFF THE GRID: Are today’s IDPs tomorrow’s refugees and migrants? 51