BERLIN (Reuters) - The wave of refugees that entered Germany in 2015-2016 has slowed its integration efforts, according to a study that also showed little progress since 2005 in leveling the playing field for immigrants on education, employment and incomes. At the height of Europe s migration crisis, Chancellor Angela Merkel adopted an open-borders policy that drew more than one million refugees into Germany in two years. In the prior decade, education opportunities picked up for newly arrived immigrants and people born in Germany with at least one foreign parent. But the Federal Statistics Office study released on Thursday found the education gap between those categories of migrants and native Germans had since widened again, with the proportion of the former lacking a high school certificate growing between 2014 and 2016. The scale of future immigration has become a major sticking point in three-party talks that Merkel is leading on the formation of a new coalition government, for which she has set an initial deadline of Thursday night. While Germany s unemployment rate has fallen to its lowest since the country s reunification in 1990, more immigrants were unemployed in 2016 than native Germans, the study said. In that year, 13.6 percent of immigrants and 6.2 percent of native Germans had low-paying jobs. Merkel s conservatives have proposed to the coalition talks that a suspension of reunifications between migrants and their family members outside Germany should be extended beyond a March 2018 deadline. Immigration expert Herbert Bruecker, a professor at the Berlin Integration and Migration Institute, said that would worsen the divide.   Our surveys show that people, who are living separated from their families, have a lower life satisfaction and also suffer more often from depression or bitterness,  he said. 