Migrant children who come to Sweden after the age of seven are drastically falling in Swedish school standards since 1998 with only half being able to pass in 2014.

The results come from a new study by the Swedish Expert Group on Public Finance (ESO) who say that test scores of children from migrant backgrounds have greatly deteriorated since 1998.

In 1998, around 70 per cent of migrant children passed grade nine – the last mandatory year of “secondary school”, signifying an important stage in Swedish pupils’ educational development. That number has gone down to only 50 per cent in 2014, according to Sweden’s Teacher’s Union paper Lärarnas Tidning.

The report claims that for migrant children who come to Sweden before the age of seven there is little change from the previous year’s results, but those who come after age seven are performing worse and worse.

Hans Grönqvist, associate professor of economics at Uppsala University and one of the authors of the report, said: “Those who have arrived in recent years have been considerably older on arrival, which means they have less time to achieve the objectives of the school.”

The authors of the study also say there are performance differences based on the geographical origin of the children, with African migrants performing the worst.

Another category of students who have struggled to meet the Swedish school requirements has been the ever increasing number of unaccompanied underage migrants. According to the figures, only 20 to 30 per cent of underage migrants meet the Swedish school standards in the subjects of Swedish, English, and mathematics.

Grönqvist explained why the unaccompanied asylum seekers performed so poorly saying: “These groups stand out in the sense that they have a very high average age at arrival in Sweden. Among the unaccompanied, the average age is just under twelve, while it is 8.5 years for the foreign-born group as a whole.”

The large influx of migrant children has also been seen as one of the reasons that Sweden has fallen in the international PISA scores which rank school systems in various countries. Of 34 countries surveyed, Sweden has dropped to 28th in mathematics, 27th in reading, and 27th in science.

The OECD wrote: “The gap between immigrants and native-born remains a challenge: almost one in two immigrant students (48%) perform below the baseline level in maths, compared with 22% for native-born students.”

In the heavily migrant-populated city of Malmo in southern Sweden, where 42 per cent of the population have foreign backgrounds, 17 per cent of the teachers in the city quit last year to move elsewhere. Many, including the teachers’ union, have said some schools have become dangerous for teachers due to widespread violence and criminality.