American Airlines Group Inc. signaled a hit from consistently high labor and fuel expenses on Wednesday and estimated first-quarter earnings below market estimates, joining rival United Airlines.

The negative outlook caused its shares to decline by more than 8% and affected other significant American airlines. The earnings season for Delta Air Lines, which begins on Thursday, dropped 2.08%.

The airline sector has been able to contain expenses by raising prices in response to increased travel throughout the world, but concerns about the sustainability of consumer demand have grown in light of high borrowing rates, inflation, and job losses.

American said in January that its fuel price had risen nearly 70%. The airline industry weathered the broader economic slowdown in the United States thanks in part to airline capacity constraints due to shortages of aircraft and spare parts.

American announced robust demand and expects total revenue per available seat mile, an indicator of pricing power, to rise about 25.5% year over year in the first quarter.

On an adjusted basis, however, the company forecast quarterly earnings per share of between 1 and 5 cents, compared to a previous forecast of near break-even and analysts’ expectation of 6 cents, according to data from Refinitiv.

“American’s updated guidance for 1Q23 came in largely in the middle of its original guidance, which was provided in January, although we expected American to come out on the better side in a similar way to JetBlue’s updated guidance, which was provided in mid-March was released,” said Raymond James analyst Savanthi Syth.