Education has long been cast as the “great equalizer” of American society. Post-secondary colleges, and in particular public universities, are especially prized as engines of upward mobility. As recent research by Raj Chetty, John Friedman, Emmanuel Saez, Nicholas Turner, and Danny Yagan shows, some institutions are more effective in this regard than others.

The new Chetty et al. study provides a treasure trove for further research. One major limitation of the data (which is available online), however, is that it cannot identify the race or ethnicity of the student, since it is drawn from administrative tax records. This matters because there are big race gaps in intergenerational mobility rates. Education is a big part of the story here: While the race gap is closing for college enrollment, it remains as stark as ever for graduation rates.

College success rates reflect, in large part, inequalities that open up long before college matriculation. As we show in our latest entry in the Social Mobility Paper series, “Race gaps in SAT scores highlight inequality and hinder upward mobility,” there are, for example, persistent race gaps on the math section of the SAT, which is an important gateway to higher education. Insofar as SAT scores predict student success in college, inequalities in SAT score distributions reflect and reinforce racial inequalities across generations.

Analyzing data published by the College Board for college-bound seniors in 2015, we find very large racial achievement gaps. Blacks and Latinos remain clustered at the very bottom of the distribution. Blacks in particular lag far behind, with an average score of 428 out of 800, significantly below the average score of 534 for whites and 598 for Asians.

These inequalities are especially concentrated at the tails of the score distribution; we estimate that at most only 1,000 blacks and 2,400 Latinos scored above a 750, compared to some 16,000 whites and 29,600 Asians. Perhaps most disappointingly, we find that the black-white score gap has remained virtually unchanged over the past 15 years, despite significant efforts to close the achievement gap.

We consider some potential explanations for these patterns: Perhaps these gaps say something about the nature of the SAT? Or the composition of test takers? Or simply reflect the different economic circumstances of racial groups? None of these seem likely to be generating such wide gaps. While there are concerns about racial bias in the SAT, these are mostly focused on the English side of tests, and we only show results for math. Nor does it look as though the results are driven by the racial composition of SAT test-takers, or that they can be primarily explained by income gaps across race.

In fact, the truncated nature of the SAT math score distribution could even suggest that these race gaps would be even larger given a harder exam with a bigger score variance. Note for example how the black score distribution is cut off at the bottom while the Asian score distribution is cut off at the top. That suggests that a redesigned exam might feature even more pronounced race gaps.

There are of course some big issues at stake here, including: the value of the SAT itself (versus for example, greater weight on GPA); the case for broader policies to take into account socioeconomic background in college admissions; the obsession with four-year college degrees; and the danger of college as a “bottleneck” in the American opportunity structure. We confine ourselves here to some straightforward data crunching. Nonetheless, as we conclude in the paper: