The global target of ensuring that all children complete primary and secondary education by 2030 is likely to be missed by more than 50 years, the United Nations agency Unesco warned last week.

In its 2016 Global Education Monitoring (GEM) report, Unesco says that this goal is now not expected to be achieved until 2084. It also reveals those countries that were furthest away from meeting the target.

The completion rate figures were taken from national and international household surveys, which asked how many people aged 20 to 22 had completed upper-secondary education.

The figures relate to each country’s own definition of “upper secondary”, which, on average, covers young people aged between 15 and 17.

The report says that Niger, where just 2 per cent of 20- to 22-year-olds had completed upper secondary education, was the country furthest away from the goal. In the UK, the completion rate was 94 per cent. The report also looks at countries’ school enrolment rates, which are often much high than completion rates.

On enrolment, there are two sets of numbers. The first is the “gross enrolment ratio”: the number of people of all ages enrolled at upper and lower secondary school as a proportion of the secondary-school-aged population.

The second is the “lower secondary adjusted net enrolment ratio”: the proportion of lower secondary-school-aged children enrolled in either primary, or lower secondary, school.

In the UK and most other developed countries, enrolment on both measures is universal or very near to universal.

In many developing countries the second ratio is higher, because it includes children in their early teens who are at primary school and may never attend secondary school.

However, many of the countries with the lowest scores on the first measure do not have data for the second, because schools do not report the ages of their pupils.

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