THE MBTA’S PARKING REVENUE increased 22 percent over the last five months compared to the same period a year ago, reinforcing the notion that theft by employees of the T’s private parking lot operator may have been tempering revenue gains.

The parking problem surfaced in February when daily revenue reports at MBTA lots didn’t match up with actual vehicle counts conducted by the agency. Two employees of the operator, LAZ Parking Ltd., were fired, but conflicting stories have emerged about what happened and the scope of the problem. The matter was referred to Attorney General Maura Healey over the summer.

At the meeting of the T’s oversight board on Monday, the issue resurfaced when Evan Rowe, the agency’s director of revenue, reported that July-through-November parking revenue totaled$9.6 million, compared to $7.86 million for the same period the year before. CommonWealth previously reported that T parking revenue also jumped in March and April after the receipt discrepancies were discovered.

Rowe said the T expects to end the fiscal year at the end of June with $21 million in parking revenue, up $2 million over the previous year.

It’s nearly impossible to say whether the increases in parking revenue came about because a theft problem was snuffed out or whether some other factors were at play. Possible factors include the weather, shifting travel patterns, and the Red Sox going from last place to first place and drawing larger crowds.

But T officials seem to be convinced LAZ is part of the problem. “We certainly believe it was not being administered appropriately by LAZ,” said John Englander, the T’s chief legal counsel. T officials said any more discussion about the contract with LAZ would have to take place in executive session. The MBTA is putting the parking management contract out to bid early.

LAZ officials declined comment, saying they would abide by a request from the attorney general’s office not to discuss the situation in the media.