In 1960, only six percent of all the doctors and lawyers in the country were either women (of all races and ethnicities) or men of color. All the rest — the overwhelming majority — were white men. Fast forward half a century. By the year 2010, women and nonwhite men were 38 percent of doctors and lawyers. A similar integration occurred in other high-paying professions that required college and post-graduate degrees.

According to a paper by economist Chang-Tai Hsieh and his co-authors, this deepening integration accounted for an astonishing 40 percent of the per-capita economic growth in the country during this period. Like much of Chang-Tai’s other work, this paper is about what happens when people are finally able to apply their talents in ways that best take advantage of those talents — and what a tragedy it is, for all of us, when they can’t.

And that’s why this story is not entirely a happy one. Mainly because there is so much progress that is still left to be made. But also because the progress that was being made appears to be slowing down. And for some people, it might even be reversing.