Nearly three in every 10 MBTA employees made $100,000 or more during 2015, according to new figures provided by the agency.
A total of 1,884, or about 29.2 percent of the 6,451 T workers who were employed by the agency as of Dec. 31 made more than $100,000 during 2015.
In addition to regular pay, many MBTA employees collected significant overtime pay. Many also received back pay, or retroactive pay raises.
The T released figures last month showing that, as of early December, 1,551 T employees, or about 23.9 percent, of the 6,482 workers employed by the agency at that time, had made more than $100,000. The new figures reflect another month of pay.
The T's employee pay data for all of 2015 also shows that the highest-paid employee — a maintenance worker — made an additional $12,295 over the last month, bumping his total compensation for the year up to $327,636. That worker's typical annual pay is $84,822, but overtime and back pay drove up his yearly take.
He was one of two employees who made more than $300,000 last year. The other was another maintenance worker who made $319,902.88, far above his typical annual rate of $109,824.
MBTA officials said the agency had taken steps to reduce its spending on employee overtime, including by rolling out new attendance policies on Jan. 1.
Those policies are aimed at reducing high rates of worker absenteeism. Agency officials said absenteeism drove up costs because workers were scheduled to work overtime hours to cover for their absent colleagues. Absences also cost the T potential revenue and caused riders inconvenience as absent operators led to dropped trips.
"Two of our critical priorities here are reducing absenteeism and overtime," T chief administrator Brian Shortsleeve said Tuesday. "We're about three weeks into the year, but it appears our new policy is having its desired impact. The trends are positive so far."
During the first half of January last year, the agency spent about $145,000 per day on average to cover employee overtime, data provided by the T shows. This year, it has spent about $112,000 per day during about the same stretch, a decrease of about 23 percent.
Shortsleeve said the goal is to average $100,000 per day in overtime spending, which would allow the T to hit its overtime budget target for the year.
The agency has also seen a decline in unscheduled absences for most types of workers so far, data shows.
Shortsleeve said the T is continuing an audit of last year's employee pay figures and is reviewing all policies to see if other steps can be taken to bring costs down. He said the findings from that work should be released in the coming weeks.
The agency also expects to look for overtime-related savings by seeking changes to contracts it has with its unionized employees once the deals are up for renegotiation. Shortsleeve said there are about 30 unions and most of the contracts expire around the spring of 2018.
There is "a set of challenges that exist within our collective bargaining agreement," he said. "There's a set of policies that, in the next round of negotiations, would help us to reduce overtime."
James O'Brien, president of the Boston Carmen's Union, which is the T's largest labor union, said that employees are forced to work overtime because the agency is not properly staffed.
"The way to solve this is to hire more people. That will solve [high] overtime," spending, he said. "If they staffed the place fully, they could reduce overtime. If they want to run it on a skeleton crew, they're going to have to pay overtime."
O'Brien said that workers who put in extra hours at the request of their managers should not be blamed. He said overtime hours are controlled by MBTA managers.
"This is a management issue," he said. "The MBTA assigns overtime. They set the schedules, the staffing levels, and assign overtime."
"When is the MBTA management going to be held accountable?" he added. "I'm tired of my employees being scapegoated."
Another factor that both T and union officials have said drove up overtime spending in 2015 was the increased need for workers to deal with last winter's record-breaking snowfall.
During 2015, members of four unions also received retroactive wages for three to five years, including promised raises and awards from contract disputes.
Overall, said Shortsleeve, the T official, the message is: "We expect we will have less people at those pay levels in 2016 than we did in 2015."