As hot new restaurants come and go, the industry is still struggling to reverse a yearslong trend of stagnating customer visits.

Not so with fast-casual chains, which continue to outshine all other dining out sectors, reveals a new report.

Long the darlings of the restaurant industry, fast-casual chains remain a bright spot, posting significant year-over-year growth in traffic even as overall restaurant visits remain stubbornly flat, reported the NPD Group, a research firm.

While that continued growth has slowed in the last year, there are no signs that it will evaporate, the report said.

Visits to fast-casual restaurants have grown 6 percent annually over the last five years, fueled in part by robust growth in the number of such outlets.

There are recent signs of a modest slowdown, NPD said, but sales are still up year over year.

The more significant comparison is with the restaurant industry in general, which posted no growth in those same quarters and showed no signs of a rebound during the year ending in May 2018.

The fast-casual sector was up 5 percent for the last year.

Based on customer visits, familiar chains like Chipotle, Panera, Panda Express and Raising Cane's Chicken Fingers were among the top-growing brands.

The fast-casual segment spans everything from Mexican and Asian cuisines to bakery cafe and gourmet burger concepts.

Not only are visits to fast-casual chains growing, but the number of venues has increased 30 percent over the past five years.

David Portalatin, vice president and food industry adviser for NPD, is fairly confident that the fast-casual segment can sustain its growth into the future.

Take California chain Everbowl, with an emphasis on fruits, vegetables and superfoods like acai, he said. New concepts such as that will likely appeal to millennials, which the industry needs to court to succeed, he said.

"Millennials are in peak career and family formation and that's when you're going to use restaurants more than any other time in your life," he said. "But this generation has brought in a different set of food values. They're in search of authenticity and purity in the food, and the sourcing, as opposed to just healthy, low-fat, low cholesterol food. So chains are appealing to that dynamic."

Lori Weisberg writes for the San Diego Union-Tribune.