US STOCKS-Futures sputter ahead of economic data; Tesla slides on growth warning

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Comcast tops revenue estimates, shares rise *

American Airlines climbs on upbeat profit forecast *

Health insures slide after Humana's dismal forecast *

Q4 GDP advance on tap at 8:30 a.m. ET *

Futures: Dow off 0.02%, S&P up 0.06%, Nasdaq up 0.15% (Updated at 7:17 a.m. ET/1217 GMT)

By Ankika Biswas and Johann M Cherian Jan 25 (Reuters) -

U.S. stock index futures were muted on Thursday, as investors focused on corporate earnings and economic data to gauge whether Wall Street's record-breaking rally is sustainable, while Tesla sank on warning of slower growth. The benchmark S&P 500 climbed to its fourth straight record high close on Wednesday, after hitting an intraday all-time high for the third time in less than a week.

However, Tesla looked set to curb the euphoria in the market after its shares lost 8.3% in premarket trading on warning that sales growth may slow sharply this year. EV makers Rivian Automotive and Lucid Group also fell 2.5% and 3.2%, respectively.

"Any significant attempt (of Tesla) to boost sales and revenue from here on will probably come at the cost of further falls in operating margin, on having to compete with BYD in China - one of its biggest markets - as well as increased competition elsewhere," said Michael Hewson, chief market analyst at CMC Markets. Tesla's growth warning could fan worries over the rich valuations of heavily weighted megacap companies, also known as the "Magnificent 7", that have been the key driver of a Wall Street rally since late 2023.

Adding to the gloom, Humana sank 13.7% as it was the latest among health insurers to forecast disappointing annual profit as the sector grapples with increasing costs. Peers like Dow-Jones component UnitedHealth and Cigna lost over 3% each.

On the data front, investors will keenly monitor fourth-quarter gross domestic product (GDP) and personal consumption expenditures advance, December durable goods and weekly jobless claims. Inflation trend, signs of weakness in the labor market and increasing chances of a soft landing are on investor radar ahead of the Federal Reserve's policy decision next week.

Traders are also betting more on a rate cut in May than in March, as per CME Group's FedWatch Tool. At 7:17 a.m. ET, Dow e-minis were down 7 points, or 0.02%, S&P 500 e-minis were up 3 points, or 0.06%, and Nasdaq 100 e-minis were up 25.75 points, or 0.15%.

Among other movers, Boeing dropped 2.8% after the U.S. Federal Aviation Administration barred the troubled planemaker from expanding production of its 737 MAX narrowbody planes. Apple slipped 0.3% after supplier STMicroelectronics forecast a more than 15% drop in first-quarter revenue, and after data showed that the iPhone-maker's smartphone shipments in China shrank 2.1% in the final quarter of 2023 from a year earlier.

American Airlines rose 4.2% as the carrier forecast largely upbeat annual profit, while Southwest Airlines gained 1.7% following narrower-than-expected fourth-quarter loss. Comcast's added 2.7% as the media giant topped quarterly revenue estimates, while IBM jumped 7.4% after forecasting full-year revenue growth above estimates.

Ford Motor shed 1.3% as the automaker expects to record a pre-tax remeasurement loss of about $1.7 billion.