The airline has 18 Max aircraft, and their grounding following two fatal accidents with Lion Air and Ethiopian Airlines meant Norwegian carried 3.36 million people last month, down 59,000.

Load factors fell 0.4 percentage points to 86.1% but despite the drop in actual numbers, revenue grew by 4%.

Chief executive Bjorn Kjos explained: “With 18 Boeing 737 Max aircraft grounded, we carried fewer passengers in May compared to the same month last year. However, our customers travel longer distances and we see a higher unit revenue.”

Capacity also increased by 4%, with the airline receiving one new Boeing 787.

Kjos added: “Following a period of significant expansion and investments, the figures show that our growth is slowing down, in line with our strategy of moving from growth to profitability.”

Norwegian’s rolling 12-month passenger figure reached 38 million, compared with 34.9 million a year ago.