WASHINGTON -- US school closures caused by the COVID-19 pandemic may slightly restrict the country's economic recovery in the long term, economists with the San Francisco Federal Reserve Bank have said.

"The children of today form the workforce of tomorrow. Hence, widespread disruptions to current learning may reduce the productivity of the economy in the long run," according to a recent paper co-authored by John Fernald, Huiyu Li and Mitchell Ochse.

School closures, particularly combined with family income loss, may lead to children's lower levels of lifetime education than pre-pandemic situation, said the report released Monday.

The economists cited a study published in 2020 that estimated school closures could reduce the number of children attaining a bachelor's degree, and increase the share by 1 percent of those failing to finish high school.

Meanwhile, the disruption may also contribute to income inequality, for lower-income families may have fewer resources to compensate for lost learning than higher-income households.

"Projections show learning disruptions could lower the annual economic output 0.25 percentage point on average over the next 70 years," they wrote, adding that "the effect is small the first 5-10 years then peaks at a loss of 0.5 percentage point in about 25 years, when children reach prime working age."