(Bloomberg) -- New York City’s subway system is suffering from a tight labor market, as a shortage of train operators and conductors make the transit network vulnerable to delays.

The Metropolitan Transportation Authority, which oversees the city’s subways, buses and commuter rails, now projects it will reach pre-pandemic staffing levels in the fourth quarter of 2022 for train conductors -- who make announcements and operate subway doors --and in early 2023 for operators who drive the trains, Demetrius Crichlow, MTA’s senior vice president for subways, said Monday during a monthly committee meeting.

Earlier this year, the transit agency anticipated reaching those staffing levels by the end of June.

“Unfortunately, the headwinds of attrition, civil service requirements and competition with city agencies have been stronger than initially projected,” Crichlow said.

The MTA, the largest mass-transit provider in the US, has had to run fewer trains because of its staffing shortage. That leaves riders frustrated over subway delays just as the MTA is struggling to increase ridership. 

The agency in April was short 675 full-time positions to provide subway service, according to MTA data. A spike in crime on the subway, violent attacks on MTA workers and several high-profile incidents -- including shootings on trains -- makes hiring a challenge.

There were 200 reported assaults on the subway in the first four months of 2022, the most for that time period since at least 1997, according to MTA data. A man was fatally shot Sunday on a Q train in an unprovoked attack and more than a dozen riders were injured when a man opened fire on a subway train last month.

The MTA has increased class sizes, decreased the training time and will add an additional class for train operators this year to help increase its workforce.

“We are going back to the original playbook of strategies to increase hiring, accelerate training and optimize the use of crews we have available to operate as much service as possible,” Crichlow said.

Crew shortages delayed 245 trains per day in April, or 3% of scheduled service, according to Crichlow. Still, that’s down from 632 trains delayed per day in December.

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