Statistic of the Month: Teacher Quality

What guarantees a high-quality teaching force?  We have examined this question from several angles in this issue, with Marc Tucker’s reflections on the second International Summit on the Teaching Profession, our review of the World Bank SABER findings on teacher policies in top-performing countries, and in Vivien Stewart’s teacher quality roundtable with Lee Sing Kong and Pasi Sahlberg.  One answer that often comes up is teacher pay.  As the argument goes, top-quality candidates will be more attracted to the field of teaching if the starting salary is competitive with those in other lines of work open to top-quality candidates, and will be more likely to remain in teaching if their salaries increase at a rate comparable to those in other professions.  Of course, salary is not the only important factor in recruiting and retaining a high quality teaching force. Other factors include having standards for accessing professional training comparable to those for getting into higher education that prepare high status professionals, providing first class professional preparation, giving teachers the same kind of scope for professional decision-making that real professionals in other fields have and trusting highly qualified teachers to do the right thing, rather than encasing them in Fordist accountability schemes.  Notwithstanding the length of this list, though, no one would deny that compensation is an important factor in recruiting and retaining a high quality teaching force.

There are many different measures of teacher pay, from a strict comparison of actual salaries in USD PPP, to percentage of per capita GDP, to a comparison of teachers’ salaries with those of workers in other fields with the same level of education in a given country.  Looking at international comparisons of teachers’ salaries and workers in the same country with the same level of education, we find that across the board in top-performing countries, teachers make about what their counterparts with a similar amount of education make.  This is particularly true for upper secondary teachers, and in the Netherlands and Finland, these teachers actually make more than other similarly-educated workers.  Across the OECD as a whole, the proportion is smaller; upper secondary teachers make just over 80 percent of what other workers make, while primary and lower secondary teachers fall shy of the 80 percent mark.  In the United States, by contrast, upper secondary teachers make just over 60 percent of what similarly-educated workers make, while primary and lower secondary teachers make even less.  Other benefits aside, it is clear that providing teachers who could go elsewhere with comparable salaries does help to retain high-quality candidates.

It is difficult to discuss teachers’ salaries without a broader discussion of the overall cost of education systems, particularly because teachers’ salaries tend to represent a majority of the spending in most education systems.  Last month, the OECD posed the question of whether money buys strong performance on PISA in one of their “PISA in Focus” briefs.  What they found was that it is not how much a country spends, but how they spend it, that correlates to higher PISA scores.  They found that once countries spend more than  $35,000 on total student expenses from the ages of 6 to 15, any additional money spent does not seem to pay off in student performance.

One of the highest-spending countries, the United States, has one of the lowest average PISA reading scores, whereas Shanghai and New Zealand, economies which both spend less than half of what the United States spends on individual students, have far better student performance. However, there is clear correlation between investment in teachers’ salaries and PISA performance. Countries in which teachers have higher purchasing power, as measured by their salaries as a proportion of GDP, also tend to have much higher student performance on PISA, as indicated by the second chart.

In many of the countries, and notably in Korea, lower secondary, mid-career teachers are paid, on average, more than the average GDP per capita.  However, while in Korea teachers are paid twice the GDP per capita, they are paid only about 80 percent of what similarly-educated workers in other fields are paid, suggesting that while teachers are paid very well compared to the average worker, their pay is still some distance from that of the highest status professionals.  Overall, the data would suggest that nations that want a first class teaching force need to be prepared to pay enough to take compensation “off the table” as a major consideration for talented young people making career decisions, but need not pay at the top of the professional scale.