Southwest Airlines said on Thursday that it would shut down its operations at Newark Liberty International Airport, as the grounding of Boeing’s 737 Max continued to take a toll on carriers in the United States.

Southwest, reporting second-quarter earnings, said that as a result of the troubled jet’s grounding, its passenger numbers had declined, its costs had increased and it had lost an estimated $175 million in profit. Operating income for the second quarter was $968 million , $4 million less than the same period the year before.

Southwest is particularly reliant on the 737 Max, and the airline had expected to take delivery of 44 of the planes this year . That was before Boeing stopped delivering the plane until it is deemed safe to fly again.

The 737 Max was grounded on March 13 shortly after the crash of an Ethiopian Airlines flight killed all 157 people on board. About five months earlier, a 737 Max plane crashed in Indonesia, killing 189 passengers.