The gross enrollment ratio (GER) is often misunderstood as a valid measure of undergraduate enrollment. In fact, the measurement of GER includes students well beyond typical undergraduate age; encompasses enrollment in associate, bachelor, master, and doctoral degrees and lacks consistency in whether international students are counted in their home or host country. This raises important concerns about the policy implications of GER measures and questions about how to develop more conceptually meaningful indicators in future.

In the world of higher education research and policy analysis, there are few data points more frequently cited than the gross enrollment ratio (GER) in higher education. Practically every analysis of national higher education systems includes reference to the ratio, as do all academic analyses of higher education massification, both internationally and within specific contexts. The figure is universally used as an indicator of the size of a national system of higher education, whether at a particular moment in time or in time series analysis, showing change over time. With very few exceptions, the measure is used to indicate growth in undergraduate education within a particular system—or to compare undergraduate enrollment figures across contexts or over time. However, the GER—at least as calculated by the UNESCO Institute of Statistics (UIS), which is the most common source of such data—is not, in fact, a valid measure of undergraduate enrollment. This widespread apparent misunderstanding of how the ratio is calculated and, therefore, what it means is problematic for research and deeply concerning for policy analysis.

What the GER Does and Does Not Measure

According to the UIS Technical Cooperation Group’s note on the measurement of Sustainable Development Goals (SDGs) indicator 4.3.2, the GER measures “total enrollment in tertiary education regardless of age expressed as a percentage of the population in the five-year age group immediately following upper secondary education.” The GER, therefore, compares the total number of people (of any age) enrolled in tertiary education in a given year to the total national population that falls in the “five-year age group” (which can vary in its definition, depending on national context, but is most commonly those between ages 18 and 23).

The first and most obvious implication of this method of calculation is that people older than 23 are included in the GER. In contrast, the net enrollment ratio (NER) captures only those people between the ages of 18 and 23 enrolled in tertiary education, compared to the entire population of the eligible age group. At lower levels of education (and in most countries), there is not a very large difference between the GER and the NER. However, at the tertiary education level, the difference can be enormous. In many countries, there is a very substantial number of people enrolled in tertiary education who are over the age of 23. As such, the GER is not a good measure of the proportion of typical university-age students attending university. When used to measure the participation of young people in tertiary education, the GER represents a significant inflation, particularly in contexts where many people enroll in tertiary education later in life. This is particularly problematic in contexts where university enrollment figures do not represent actual participation (for example, in Greece, where many people remain technically enrolled in tertiary education long after concluding their studies, in order to maintain certain social benefits). However, the NER is almost never calculated or reported. Rather, researchers and policy analysts alike tend to rely on GER data to represent the size of the tertiary education system.

Much more problematic is the fact that “tertiary education,” for the purposes of the GER calculation, includes all people enrolled in International Standard Classification of Education (ISCED) levels 5, 6, 7 and 8. In other words, the GER is not a measure of undergraduate education. Rather, it includes all individuals enrolled in associate, bachelor, master, or doctoral degrees. When used as a proxy measure of undergraduate education, therefore, the GER is deeply misleading. It also significantly limits the utility of cross-country comparison, given that many countries have very little postgraduate education, whereas others enroll thousands of students at postgraduate levels. Crudely combining enrollments at different levels of tertiary education also makes it very difficult to capture massification trends over time (i.e., by tracking whether expansion at the undergraduate level eventually leads to expansion in enrollment at postgraduate levels). The incorporation of postgraduate education also adds further concerns to the point raised above, regarding overinflation of the GER. Although there is not an equivalent “standard age group” for postgraduate education, in no country would it be typical for 18-year-olds to be enrolled in master programs. It is worth noting that UIS does hold data on enrollment numbers by ISCED levels 5, 6, 7, and 8, which would enable a disaggregated calculation. In its present form though, the incorporation of postgraduate students in the GER further inflates the figures we currently use.

Finally, it is very unclear if (and, if so, how) international students are included in calculations of GER. There is no guidance on this point in the UIS guidelines, which suggests that countries may in fact make different choices about whether or not to include international students in their calculations. One would assume that those enrolled in full degree programs outside their home country would be captured in the total enrollment figures of their host country but would be more likely to figure in the population numbers of their home country. UIS does collect separate data on internationally mobile students, both by outbound and inbound country. However, their incorporation in GER calculations is unclear, and countries are likely making different determinations on this point, which raises further complications for cross-country comparison.

Towards a More Useful (Set of) Measure(s)

As tertiary education expands around the world—and as governments increasingly invest in their expansion—it is vital that we find a better way to capture participation. At a minimum, it seems clear that we need to move away from combining all levels of tertiary education and to instead calculate the GER in each individual level separately. However, there remain significant challenges. What is the “typical” age group for postgraduate education, for example? How do we handle international students, especially given that, by definition, international students affect reported numbers in at least two different countries?

Even beyond these significant technical challenges, the most pressing question is what we think these measures show us. Are we interested purely in the growth of the (national) higher education sector, year on year? If so, we could just capture enrollment numbers over time, without converting them into a ratio. Or are we more interested in how much of our population is educated to the tertiary education level? If so, the current method of calculation does not capture that, as we are only looking at enrollment figures for a specific year. In order to determine this proportion, we would need to calculate the percentage of the total population that has ever attended tertiary education—a potentially more challenging indicator to capture but one that would have far more useful explanatory power. The GER does show us something, but it does not generally show us what we think it shows us. Moving towards new measures seems like an important—even pressing—priority.

Ultimately, we need to acknowledge that indicators are not purely technical. Defining what the best indicators are—and how best to calculate them—is a conceptual exercise that should involve multiple stakeholders, who are invested in how indicators can be used. In the meantime, we at least need to inform ourselves about how the current indicators are currently calculated, and reframe our research and policy conclusions accordingly.

Rebecca Schendel is managing director of the Center for International Higher Education at Boston College, United States. E-mail: [email protected].

Benjamin Alcott is associate professor at the Institute of Education, University College London, United Kingdom. E-mail: [email protected].