Why a School Completion Rate Can Be 148% — Reading the Statistic Properly
Seventeen of 189 countries report secondary figures above 100%. Not an error — it is a gross enrolment ratio, and that changes which comparisons are valid.
Seventeen of the 189 countries with a published figure report secondary completion above 100%, reaching about 148% in Monaco, because the measure is a gross enrolment ratio that counts repeating and over-age students.
The secondary completion figure for Monaco is about 148%. This is not a typographical error and it is not a country being unusually good at school.
It is a measure being read as something it is not, and the same misreading quietly breaks a lot of country comparisons.
What the number actually is
Most published school completion figures are gross enrolment ratios. The calculation is:
everyone enrolled at that level ÷ the population of the official age group for that level
The numerator counts everybody in secondary education. The denominator counts only people of secondary-school age. So anyone enrolled who is older than the official age band, or repeating a year, is counted on the top and not the bottom.
Enough of them, and the ratio passes 100%.
Where that leaves the rankings
| Countries with a published figure | 189 of 194 |
|---|---|
| Reporting above 100% | 17 |
| Highest | Monaco, ~148% |
| Highest at or below 100% | Bahrain, Croatia, Luxembourg, ~100% |
| World average | ~60% |
| Lowest | Central African Republic, ~9% |
Two practical consequences.
A high ratio is ambiguous. It can mean near-universal participation. It can also mean a large cohort repeating years, which is a sign of strain rather than success. The number alone does not distinguish them.
A low ratio is not ambiguous at all. Nine percent means nine percent. The bottom of this table is measuring something real and the top is measuring something mixed, which is the opposite of how rankings are usually read.
The two other education measures worth reading carefully
Compulsory years of schooling runs from 5 to 15 years. The top is a five-way tie — Israel, Mexico, Tonga, the Dominican Republic and El Salvador all mandate fifteen — and the bottom is Bangladesh, Madagascar and Myanmar at five. Any list naming a single country as "longest" is picking one of five arbitrarily.
School starting age runs from 4 to 7. The United Kingdom and Ireland start earliest; Ethiopia, Tanzania, South Africa and Mali start at seven. As is four too young to start school sets out, the outcome evidence does not favour the earlier end.
How to use these figures without misleading anyone
- Say which measure you are quoting. "Gross enrolment ratio" and "completion rate" are used interchangeably in press coverage and are not the same thing.
- Do not rank the top. Above about 95% the differences are mostly measurement artefacts.
- Do rank the bottom. That end is where the number carries real information.
- Check the denominator year. Population estimates get revised, and a ratio moves when its denominator does without anything happening in a single school.
See every country at secondary school completion by country, the wider set at school enrolment statistics, or what happens where the cohort is shrinking at falling school rolls.