Delta Air Lines is raising $9 billion in a massive debt sale backed by its frequent flyer program, the latest large offering by an airline grappling with the coronavirus pandemic‘s impact on travel demand.

The amount is nearly 40% more than the $6.5 billion Delta said earlier this week it intended to raise. The Atlanta-based carrier is burning about $27 million a day as the pandemic continues to sap travel demand, CFO Paul Jacobson said at an investor conference last week.

Airlines are increasingly turning to their loyalty programs to raise cash after revenue from air travel dropped sharply this year. United Airlines is using its MileagePlus program to back new debt, while American Airlines plans to use its AAdvantage program as collateral for a government loan. 

Delta shares lost 1.8% to end the day at $33.96.