The rapid expansion of higher education is not limited to this country alone. According to Dirk Van Damme of the OECD’s educationtoday blog, it is an international phenomenon:

“Across OECD countries in 2012, 32% of 25-64 year-olds – over 220 million individuals – held a tertiary degree. Among young adults, the proportion is even higher: 40%. Never before have so many people attained that level of education. Just 12 years earlier, only 22% of 25-64 year-olds had a tertiary education. The tertiary attainment rate among 25-34 year-olds grew by an average of 3.4% per year between 2000 and 2012, and in most countries, it is not likely to slow down anytime soon.”

Is it worth it though?

“Some commentators doubt it; they point to the risk of over-schooling, of skills mismatches, of high-qualified workers stealing the jobs of mid- and low-qualified adults. Some governments want to contain the increasing numbers of students and build the case for a more selective tertiary education system.”

An important indicator is the graduate wage premium – i.e. the additional power that a degree gets you relative to “upper secondary education attainment.” Van Damme’s post features a graph from the OECD’s Education at a Glance 2014 report which, for each OECD member nation, plots the average graduate wage premium against the share of graduates as a percentage of the population.

The overall trend shown by the comparison is that “the greater the share of college graduates the smaller the wage premium for younger workers.” It’s not an especially strong correlation and the outliers are rather interesting.

For instance, both the UK and the US have high participation rates (between 40 and 45 per cent), but also high graduate earning premiums – which, at face value, suggests that in these countries it is, on average, worth going to university even with the expansion of the system.

Van Damme suggests that other factors might be at work:

“…the wage premium tends to be relatively high in the more open and market-oriented economies like the United States or the United Kingdom. In contrast, more egalitarian Nordic countries have a compressed wage structure where the relative wage premium for higher educational attainment is lower.”

It would be interesting to see to what extent the average wage premia in Britain and America are skewed by the best-paid graduates – and how high a proportion of the less well-paid graduates would be better off going straight from school to work.

However, it occurs to me that there’s another way of interpreting these patterns. According to the QS World University Rankings system, American and British institutions account for seventeen of the top twenty universities in the world – and all of the top ten.

Therefore instead of income inequality explaining why US and UK graduates seem to earn so well, it could be that the causality runs in the other direction – i.e. income inequality is high in these countries because the academic education is particularly good (at least for the high-fliers), while vocational education is not nearly so good.

Van Damme is at pains to stress the uncertainties in these comparisons, but perhaps the lesson for us in the UK is this: that we should celebrate our status as an academic superpower, but pay a lot more attention to the vocational side of our education system.