Tidewater keeps generating free cash flow, despite the losses piling up in a difficult offshore market.

After the close on Thursday, the Houston-based owner of the world's largest offshore fleet reported a $35.3m loss for the first three months of 2021, versus an $18.4m deficit for the same period last year.

New York-listed Tidewater's revenue was down, too, with the $83.5m reported for the most recent quarter representing a drop from $116m for the first three months of 2020.

But chief executive Quintin Kneen trumpeted Tidewater's continued generation of free cash flow, which the company has been emphasising since the Covid-19 pandemic took hold last year

"In the first quarter of 2021, we generated $19.2m of free cash flow and for the trailing 12 months, which were the most difficult the company has ever seen, we generated $87.1m of free cash flow," he said in a statement alongside earnings.

"Since late 2018, we have dedicated ourselves to building an offshore vessel company that is able to generate positive free cash flow throughout the business cycle by optimising the earnings potential of the fleet, being the lowest cost operator and by adroitly managing drydocks and capital investments."

Last year, the company had expected to generate $62m in free cash flow.

The figure came in at $52.7m, but would have exceeded the goal if not for Mexico's state-run oil company — Petroleos Mexicanos — owing Tidewater $18m.

Kneen described the debt as an annoyance, but not a cause for concern.

Day rates remain depressed, though, as Tidewater's fleet earned an average of $9,993 per day for the quarter, lower than each quarter last year.

Average day rates for its ships in the Americas were improved year-over-year, with the company reporting $11,865 per day for the first quarter of 2021 against $11,854 for the first three months of 2020.

Tidewater also reported lower vessel operating costs: $61m for the first quarter in 2021 in comparison to $78.7m for the first three months of 2020.

The company also continued to scrap ships, disposing of six for $11m.

Tidewater's New York Stock Exchange-listed shares jumped $0.38 to $13.82 during the trading day on Thursday, but lost nearly all its gains in after-hours trading, falling $0.32.