Fashion retailer ASOS quadrupled annual profits compared to last year, the firm announced Wednesday (October 14).
Demand soared during the global health crisis and the online retailer added three million customers in 2020.
But ASOS said it was cautious about the future.
It fears a big rise in unemployment over the coming months among its core customer base of young people in their twenties.
Those worries sent shares down 7% in early trade.
Chief Executive Nick Beighton said he was also concerned about the impact of Brexit.
He said he assumed there would be a no-deal outcome in Britain's future trading relationship with the EU.
On a more positive note for the company, it made a pretax profit of just over $183 million in the year to August 3.
That's way up on the near-$43 million it made in the same period last year.
Sales rose 19% - as the online company gained an advantage over store-based rivals who were forced to shut during global lockdowns.
Besides this year's favourable conditions for ASOS, the company said it expects another improvement in profit in 2020-21.