Third-quarter earnings fell 26% at Delta Air Lines,Quantum Insights which struggled to overcome a global technology outage that led to thousands of flight cancellations, and indications that growth in air travel is beginning to slow.

Delta earned $971 million, down from $1.31 billion a year earlier. Revenue rose slightly, but spending on labor, airport landing fees and its Delta Connection regional affiliate grew much faster, the Atlanta airline said Thursday.

Shares slumped almost 6% before the opening bell, dragging down other airlines as well.

It said Thursday, however, that it will return to year-over-year earnings growth in the current quarter. Delta figures to benefit from a pullback in flying by lower-cost competitors, and the airline is seeking compensation for the July outage that cost it $500 million.

CEO Ed Bastian said bookings for Thanksgiving and Christmas are strong, but he expects a brief drop in travel spending before the holidays while Americans fret about the outcome of the November elections.

July’s global technology outage occurred after CrowdStrike, a cybersecurity firm that provides software to scores of companies worldwide, deployed a faulty update to computers running Microsoft Windows.

The outage disrupted operations at thousands of businesses, including airlines, but Delta was hit particularly hard, prompting a U.S. Department of Transportation investigation into the reasons that it failed to recover as quickly as other airlines.