(Bloomberg) -- Wall Street analysts are souring on Frontier Group Holdings Inc. as a stark decline in traveler demand and elevated fuel costs worsen the airline’s earnings outlook.

The budget-friendly airline wrapped up nine consecutive weeks of declines, marking the longest losing streak in the company’s history. The previous record for underperformance had been five consecutive weeks in December 2022. The shares have fallen over 15% since Monday’s session for the worst week since early February.

Frontier, along with peer Spirit Airlines Inc., warned last week that consumers have throttled back spending on travel as high inflation crimps household budgets. Spirit also announced fare discounts ahead of the Thanksgiving holiday as it slashed revenue and adjusted operating margin forecasts, while Frontier noted a “significant unexpected change” in bookings and below-trend sales. 

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The gloomy outlook is causing analysts to turn less bullish than they’ve ever been on Frontier. Just this week, Evercore ISI cut its recommendation of the stock to in-line from outperform citing weaker revenue and margin trends. Citi pointed to sluggish forward-looking domestic booking curve data and management’s expectation for seasonal demand weakness for its rating downgrade to neutral from buy. Citi also reduced its price target for the carrier to a Street-low $5.50.

“Although the weak share price performance somewhat shields Frontier from a more bearish view, management’s demand comments, along with weak December booking curve data, now seem to leave little recourse but to downgrade Frontier from buy to neutral and add a high risk rating on increased earnings and share price volatility,” Citi analyst Stephen Trent wrote in a research note dated Sept. 20.

Demand for domestic trips is slipping while industry capacity and fuel costs are on the rise, a combination that several carriers have said is hurting their bottom lines. Benchmark brent crude traded at around $93.61 a barrel on Friday, climbing about 25% since the start of July. 

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Frontier’s 54% year-to-date descent has made it the worst-performing holding among the US Global JETS Index by far, with second-worst Hawaiian Holdings Inc. suffering a 34% plunge during the same period.

A mix of overcapacity, a struggling domestic market and rising fuel costs suggest that Frontier could swing to a loss in the third-quarter, according to Bloomberg Intelligence, as the carrier’s guidance shows capacity may grow 20%-21% versus the year-ago period, and average fares could fall 25% to $43. 

“Pre-tax margin should turn back negative in the third-quarter as per guidance, and hopes for profits in the fourth-quarter depend on holidays demand, which could disappoint,” said Bloomberg Intelligence analyst Francois Duflot.

--With assistance from Bre Bradham and Rheaa Rao.

(Updates price moves throughout and superlatives in the second paragraph.)

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