Uber has revealed the cost of a damaging driver shortage as it said heavy incentives to coax drivers back on the road meant it was making less money from each ride.

The US tech company said it had more than doubled revenues in the second quarter, as vaccinations encouraged more passengers to head to restaurants and airports.

However, it revealed that the “take rate” – the percentage of customer spending that the app takes on each ride – had fallen, from 21.5pc three months ago to 18.7pc.

Making more money from each ride is crucial for Uber as the company attempts to push its business into profit after more than a decade of annual losses.

Although passengers have been eager to return to Uber as lockdowns lift and travel reopens, the company has had to resort to substantial incentives such as bonus payments to encourage drivers back on the road. 

Dara Khosrowshahi, its chief executive, said that 420,000 more drivers and food delivery couriers were on the road than in February and that it had made “strong progress”.

However, shares fell in after-hours trading as the company also said it expects growth to slow down in the coming quarter. 

Delivery arm UberEats has accounted for most of Uber's sales in recent months. The firm has sought to capitalise by expanding into areas such as grocery deliveries

Chief financial officer Nelson Pichai predicted that total spending on Uber’s app would be between $22bn and $24bn (£16bn-17bn) in the third quarter of the year, barely above the $21.9bn in the second quarter.

Uber lost $6.8bn last year as revenues from its core minicab operation slumped, despite lockdowns turbocharging its takeaway business, UberEats. 

The delivery arm has accounted for most of its sales in recent months, and the company has sought to capitalise by expanding into areas such as grocery deliveries.

It said on Wednesday that revenues from its rides business had grown 106pc year on year, while its delivery business grew by 122pc. In total, sales climbed by 105pc to $3.9bn.

The company made a rare profit, due to gains on investments in Didi, the recently-floated Chinese ride-hailing app, and self-driving company Aurora. On an adjusted Ebitda basis, a measure of profitability closely watched by investors, it narrowed losses to $509m from $837m a year ago.

Shares fell by more than 7pc in late trading after the results.

Uber, which went public in 2019 in the biggest US listing for five years, struggled in the months since its initial public offering, but has regained its value during the pandemic, amid growing optimism over the future of its food delivery arm.

It has also sold off experimental units that were once seen as its future, such as its driverless car business, air taxi operation and its electric bikes and scooter rental service.