Newly released data from New Jersey Transit shows that May was the agency’s worst period for delays and cancellations.

The report shows that only around 87 percent of all NJ Transit trains were on time during the month of May. Of the 18,000 trains that operated, about 2,400 were delayed.

Peak-hour trains were off schedule more often than non-peak-hour trains. Only 78 percent of peak trains were on time, the agency says. Weekend riders saw nearly 100 percent on-time performances.

But when factoring in only trains that travel into and out of New York Penn Station, it was found that only 46 percent of morning peak-hour trains were on time. Evening trains fared better with 72 percent on time.

New Jersey Transit has been plagued by transit issues over the last few months. The issues became so bad that New Jersey lawmakers held hearings about the issues and Amtrak pushed forward its timetable for the Northeast Corridor improvement project.

Northeast Corridor trains had the worst record with 78.7 percent of trains on time during May. The Pascack Valley Line had the best with 97.1 percent of trains on time.

NJ Transit says that “on time” is any train that’s no more than six minutes late.