(Bloomberg) -- Boeing Co. raised around $21 billion in an expanded share sale, one of the largest ever by a public company, shoring up its balance sheet as it seeks to stave off a potential credit rating downgrade to junk.

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The US planemaker sold 112.5 million common shares for $143 each, according to a statement. The stock was priced at a discount of about 7.7% to the Friday closing price of $155.01. Boeing also sold $5 billion of depositary shares.

The company’s stock was down 0.5% in pre-market trading. It’s plunged about 42% this year, the second worst performance in the Dow Jones Industrial Average.

The infusion of funds clears one of new Chief Executive Officer Kelly Ortberg’s most urgent tasks amid a period of financial turmoil for the planemaker. Boeing’s balance sheet was already strained by the pandemic, and before that two fatal jet crashes involving its workhorse 737 Max model. Now there’s a labor strike, in its seventh week, that’s crippling manufacturing of the jetliner.

Boeing needed the capital infusion to maintain its investment-grade rating and fund its jet production ramp-up once the walkout ends.

The company is on track to burn around $4 billion in cash during the fourth quarter, which would bring its cash outflows to around $14 billion for the year. The planemaker expects to continue burning cash through the first half of next year as it restarts its factories, including the 737 Max assembly lines.

Boeing factory workers voted last week to reject the company’s latest contract offer, which included a wage increase of 35% spread over four years. The company plans to cut its workforce by about 10%, Ortberg said in a memo to employees Oct. 11.

The company on Oct. 23 received clearance from the US Securities and Exchange Commission to sell as much as $25 billion of equity and debt. Boeing also has a separate new credit agreement in place for $10 billion, giving it “additional short-term access to liquidity as we navigate through a challenging environment.”

Ortberg is also considering options to streamline Boeing’s broad portfolio. He has launched a review of its businesses that the CEO expects to conclude by year-end. The company is weighing options for the future of its troubled Starliner space capsule program as part of the review, Bloomberg News has reported.