THE MBTA ASSESSED record-level fines on its commuter rail operator in fiscal 2018, but Keolis Commuter Services said the penalties are not as severe as they appear because the company is running a lot more trains than it has in the past and fines have increased with inflation.

Keolis paid $8.2 million in fines, mostly for trains arriving late and for failing to have the required number of locomotives and coaches available for daily service. Keolis paid fines of $7.9 million, $6.9 million, and $8 million in the three previous fiscal years.

MBTA officials say they plowed $4 million of the fines in fiscal 2018 back into commuter rail operations, primarily by adding conductors to improve service.

Tory Mazzola, a Keolis spokesman, said the number of trains running without incurring a penalty has increased on a percentage basis because the number of trains the company is running rose from 139,000 in fiscal 2015 to around 150,000 the three following years. The percentage was just under 85 percent in fiscal 2015, the year of the massive snowfall, and rose to the low 90-percent range during the three subsequent years. That means close to one out of every 10 trains incurs some penalty.

Mazzola also said the dollar amount of the fines is not the most reliable indicator of Keolis’s performance because the dollar amount has increased each year. In fiscal 2015, for example, a train anywhere from 5 to 10 minutes late would incur a penalty of $500. That fine increases 2.5 percent a year.

“We are at historically low levels [of penalties], particularly when you consider we ran approximately 10,000 more trains last year compared to the first year,” Mazzola said in an email. “This reflects the positive progress Keolis and the MBTA have made for passengers with investments into the network and organization. There is more work to do, however. Hundreds of millions of dollars have been invested into locomotive overhauls, operational improvements, and infrastructure upgrades. These are contributing to an improving passenger experience, including on-time performance, and as a result lower penalty levels compared to when we first took over in 2014.”

At recent meetings of the Fiscal and Management Control Board, T and Keolis officials have reported significant progress in addressing on-time performance and equipment availability. Still, the amount of fines in fiscal 2018 indicates there has been some slippage. The fines hit their highest level ever in fiscal 2018, up sharply from fiscal 2016, even though the number of trains running was roughly the same. In fiscal 2016, 93.54 percent of the 150,429 trains ran with no penalty, while 91.85 percent of the 150,203 trains ran with no penalty in fiscal 2018, Keolis said.

Mazzola said the 10-year commuter rail on-time performance average was 87 percent, but it rose to an average of 89 percent in [calendar year] 2016, 2017, and so far in 2018. “The trend is moving in the right direction for our passengers,” Mazzola said.

He credited repair work that has increased locomotive availability by 26 percent since 2014 and noted that, on average, 28 more coaches per day are available now compared to 2014.