American Airlines‘ chief financial officer said Thursday that some travelers are avoiding Newark Liberty International Airport for other options in the area after a spate of recent disruptions, but cautioned that the impact is “modest.”

“There probably is some amount of book-away from Newark flights over into LaGuardia, JFK, maybe Philadelphia to a lesser extent,” CFO Devon May said at the Wolfe Research conference.

The Federal Aviation Administration this week ordered airlines to temporarily cut flights at Newark to relieve congestion there as carriers grapple with a shortage of air traffic controllers, equipment outages and runway construction at the New Jersey airport. Bad weather has also added to disruptions in recent weeks.

American has a roughly 4% market share at Newark, according to the most recent data from the Port Authority of New York and New Jersey, which operates the airport along with LaGuardia Airport and John F. Kennedy International Airport, both in Queens, New York.

“There’s something happening there, but I think it’s relatively modest when you think of the broader network,” American’s May said.

United Airlines dwarfs all other airlines at Newark with its nearly 70% share. That carrier had proactively announced cuts of 35 flights a day earlier this month to put more slack in the system.

Earlier this month, Transportation Secretary Sean Duffy said the U.S. will spend billions to overhaul the aging U.S. air traffic control system.

President Donald Trump’s tax bill, which passed the House early Thursday includes $12.5 billion for air traffic control modernization and staffing.