Two refugees from Syria wait in front of a registration office for asylum seekers in Berlin. (Carsten Koall/Getty Images)

If 2015 was the year in which Germany opened its doors to refugees, 2016 was when the country pondered how to close them. Although the influx of refugees peaked more than a year ago, attacks like the one in Berlin on Dec. 19 have led to demands that Germany refuse entry to individuals without passports and step up deportations of criminals and terrorism suspects.

Authorities hope that another trend will have a bigger effect in the short run: migrants deciding to go back because they are fed up with Germany or fear deportation. More than twice as many migrants departed the country voluntarily this year than were deported.

Out of the 55,000 migrants who left voluntarily, 15,000 were Albanians. About 5,000 each from Serbia, Iraq and Kosovo returned home. The numbers were first reported by Germany's Sueddeutsche Zeitung newspaper. A spokesman for the migration ministry confirmed the numbers on Wednesday.

Germany offers individuals or families willing to return to their countries of origin financial benefits that can amount to several thousands of euros, including travel costs and start-up grants. Promoted as an alternative to conventional development aid, such payments are supposed to help vitalize local economies and to prevent returnees and others from again fleeing to European Union nations.

The German government will spend more than $155 million on additional development aid projects over the next three years in countries that are home to many of the migrants who head to Germany. Among the nations included are Morocco and Tunisia, as well as Kosovo, Serbia and Albania, all countries generally considered “safe” by German authorities.

Voluntary departures are unlikely to make up for Germany's lagging efforts to deport more migrants, however. Out of the almost 900,000 people who entered last year alone, many remain in the country despite being refused asylum.

An airplane of Meridiana airline, chartered to deport refugees back to Afghanistan prepares to take off at the airport in Frankfurt am Main, western Germany on December 14, 2016. / AFP PHOTO / DANIEL ROLANDDANIEL ROLAND/AFP/Getty Images An airplane chartered to deport refugees back to Afghanistan prepares for takeoff at the Frankfurt airport. (Daniel Roland/AFP via Getty Images)

German authorities say deportations are expensive and difficult to organize. Migrants are often arrested at night and later put on planes to their home countries.

Pressure to change that process is increasing as more details are emerging about efforts to deport Anis Amri, the man suspected in the Dec. 19 Berlin market attack, which killed 12 people. The fugitive was fatally shot by a police officer in Italy.

Despite the 24-year-old’s criminal past, he  could not be deported to his home country of Tunisia for months because he lacked documents, which the North African nation had failed to provide, according to German media reports.

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