THE  MBTA’S subway operations control center is a microcosm of the challenges facing the transit authority.

Last June, the Federal Transit Administration issued an initial safety report that said the control center was understaffed, leading to dangerously long work days .

To deal with the situation, the T scaled back subway service to weekend levels (a 20 percent reduction) to match the existing staffing level, and then set about hiring up. But when the T finally reached its staffing goal, it discovered it didn’t have enough subway operators to return to full service.

A new report from the Massachusetts Taxpayers Foundation suggests inadequate staffing levels have become the T’s biggest challenge and perhaps the most difficult one to resolve.

The numbers are not pretty. According to the foundation, the T needs to hire 2,800 people in the next 12 months to achieve a net gain of 1,800. The odds of reaching that goal are not good because as fast as new employees come in one door existing employees are walking out another.

In the first nine months of the current fiscal year, the T hired 690 people but had 522 departures, for a net gain of just 168.

From 2019 to 2022, the T hired 2,400 people but that resulted in a net gain of only 450 because so many existing employees left.

“It’s not that they haven’t made progress in the rate of hiring” said Doug Howgate, president of the Massachusetts Taxpayers Foundation. “It’s that when you lose five people for every six you hire the problem isn’t going away.”

Since fiscal 2020, the MBTA has had job vacancy rates exceeding 10 percent every year, according to the report.

The implications are enormous. Without adequate staff, the T cannot restore full service, cannot expand into new areas, cannot complete capital projects, and cannot reach its safety objectives.

The Taxpayers Foundation report highlights ways to improve the situation, but notes the MBTA is facing an uphill struggle.

The problem began when the MBTA implemented a hiring freeze and reduced its headcount by 10 percent between fiscal 2015 and fiscal 2018 to help balance its budget.

Now, as the T is scrambling to build back its workforce, the Taxpayers Foundation said the transit authority needs adequate funding and a streamlined hiring process. But simply attracting more workers may not be enough as members of its aging workforce retire.

In the first eight months of fiscal 2023, 199, or 40 percent, of the 462 departures at the MBTA were retirements.

As the state’s population shrinks and ages, what’s happening at the T is also happening in other industries.

“Labor shortages pose a statewide challenge that is getting worse,” the Taxpayers Foundation report said. “The impacts of workforce gaps extend beyond public transit to hospitals, pharmacies, manufacturers, nursing homes, schools, restaurants, and many more that must cope with staffing shortages, reduced hours, and lower capacities.”

Given the high cost of living in Massachusetts, there’s no easy fix. The Taxpayers Foundation suggests a coordinated statewide effort to address the problem.

“The state’s approach to workforce challenges has been underwhelming, lacking coordination and scale,” according to the foundation report. “The task to attract talent has historically been left to the premier financial, academic, and health institutions in the state. Given the changing geographical relationship between employers and employees and reduced college enrollments, leaving these institutions on their own to promote the state will no longer suffice.”