The United Auto Workers (UAW) strike against Detroit's three major automakers has entered its fourth week, causing more damage to the U.S. economy than any auto industry strike this century. The U.S. auto workers' strike that began on September 15 is still ongoing, with the number of workers participating in the strike reaching approximately 25,000. The UAW said on Friday that it would not expand the scope of the strike for the time being because negotiations with manufacturers have made "significant progress", but it has not yet reached the auto union's ultimate goal.

Michigan economic consulting firm Anderson Economic Group (AEG) reported on Monday that by the end of the third week, the cost of the auto union's strikes against Ford, General Motors and Stellantis had reached $5.5 billion, surpassing the previous record of $4 billion.

In 2019, the UAW strike against General Motors lasted for 40 days and caused an estimated $4 billion in losses to the economy.

Data show that the UAW's strike against the Big Three has caused workers to lose $579 million in wages, while automakers have lost a total of $2.68 billion, dealers and customers have lost $1.26 billion, and suppliers have lost $1.6 billion.

"Losses in the third week were higher than the previous two weeks as we saw more factory closures and dealers reporting parts shortages," AEG principal and CEO Patrick Anderson said in a statement. He added, "The pressure on parts suppliers has become very serious, and more than 30% of suppliers said they have started to lay off employees."

AEG noted that a recent survey by automotive suppliers association MEMA found that "nearly 30% of surveyed auto parts suppliers have laid off some directly employed employees as a result of the strike," and that "other suppliers will begin layoffs, with more than 60% expecting to begin layoffs by mid-October."

Ford warned in the second week of the strike that as many as 500,000 supplier workers could be laid off if the strike continues. Automakers have laid off thousands of their own workers due to shutdowns at some plants.

U.S. economists have warned that a strike lasting a month or longer could affect the U.S. gross domestic product and increase the risk of a recession.