This allowed the researchers to see how women’s suffrage (or lack thereof) affected long-term outcomes for kids—including how long they stayed in school, their literacy levels, and their eventual income. They controlled for other factors that could have muddled the results, including compulsory-school-attendance laws and the New Deal. Those results are summarized in the working paper, which was recently published by the National Bureau of Economic Research.

Education isn’t the key to a good income.

Shenhav and her team found that suffrage increased local education expenditures by 9 percent on average and corresponded with a rise in school enrollment. These trends were more pronounced in cities that had high shares of African American residents, were located in the country’s South, and/or had low rates of per-capita spending on education and other social services to begin with. For black students, “full exposure to suffrage”—i.e., being born after or only shortly before the women’s right to vote became the norm—led to nearly an additional year of education. “The effects of suffrage,” the economists write, “are akin to the one-year increase in attainment of black students from court-ordered desegregation.”

For white students, the increased education amounted to a statistically insignificant 0.10 years, though white children in the South gained an additional 0.96 years in school. The gains were generally comparable between boys and girls—though they were more pronounced among black boys than for black girls.

Taken together, these findings suggest that women’s suffrage helped reduce the precursor to the modern-day achievement gap. And in chipping away at those disparities, the economists conclude, women’s suffrage may have had a longer-term impact on the income prospects of some children. “It appears that one of the main benefits of suffrage may have been to help raise the bottom and middle of the distribution of historically less-educated communities,” the researchers write.

The findings suggest that white students in the South whose formative schooling years happened after the Nineteenth Amendment’s ratification saw their incomes increase by 34 percent thanks to the law. Similar effects were not found among white students outside the South or among African Americans, but the authors point to numerous potential reasons for the discrepancy, including the fact that black workers received fewer returns in exchange for their skills in the labor market and were exposed to lower-quality education, especially in the segregated South.

In securing women the right to vote, the Nineteenth Amendment seems to have produced a positive, long-lasting contagion effect throughout society. “One of the ongoing things that we’re learning as economists is that there are spillovers from policies that are not necessarily targeted to education,” Shenhav says. “Policies that reduce political participation have implications for education policy.”