The Labor Department’s new proposal to update the overtime-pay rules would give millions of American workers a toehold in the middle class. By raising the salary threshold for overtime, which has barely budged since 1975, nearly five million more people would start earning overtime pay, according to White House estimates.

The new rules would also help remedy a severe imbalance in the economy. Since 1979, pay for the median worker has risen only 9 percent even as worker productivity has grown 64 percent. Theoretically, productivity gains should translate into higher pay, allowing the middle class to grow and prosper. But that hasn’t happened, in large part because many employees are not paid time-and-a-half when they work more than 40 hours a week.

Under current rules, salaried workers are not eligible for overtime if they earn enough to qualify as executives, professionals or administrators. The proposal would raise the salary threshold that defines those positions. Today, employees can be considered part of the top ranks — and generally ineligible for overtime — once their salary reaches a paltry $455 a week, or $23,660 a year. The new threshold in 2016 would be $970 a week, or $50,440 a year, about where it would be if it had kept pace with inflation over the decades. At or below that level, salaried workers are automatically eligible for overtime. (The current rules for hourly workers would remain intact.)

If a business does not want to pay the newly required overtime, it could hold salaried employees to 40 hours a week. That would not harm the employees, because they are not paid by the hour; rather, it would give them more time off at no less pay. And if employers hire new employees to do work previously performed by those who put in unpaid overtime, the economy would benefit from the added job growth.