The number of people with an immigrant background in Germany reached a new high of 18.6 million in 2016.

Data from the Federal Statistics Office released on Tuesday shows that just over a fifth of the country’s population are first or second generation immigrants, with at least one parent born without German citizenship.

Half the 18.6 million considered to have an immigration background are German nationals, including 5.1m immigrants and 4.4m who were born in the country.

The other half are foreigners. Their number has grown from 4.9 million in 2011 to 7.6 million last year, an increase driven by the influx of refugees into the Germany.

The figures come in the build-up to elections in September. Chancellor Angela Merkel’s decision in 2015 to open borders to more than a million migrants initially hit her popularity, although her CDU party has since largely recovered.