Between 40,000 and 50,000 U.S. retail stores will close over the next five years, according to an estimate by financial services giant UBS, as reported by CNBC. Though that represents further pain for the retail sector, the estimate is actually more optimistic than UBS was about a year ago, when the company forecast 80,000 store closures over five years.

The revised estimate assumes annual retail sales growth over the next five years of about 4% and that e-commerce's share of retail sales will be 25% by 2026, up from 18% last year.

Larger shopping malls are more at risk from the coming wave of closures than neighborhood shopping centers, UBS said. Foot traffic to malls has taken a hit in recent years as anchors close, and even more recently as the price of gasoline has spiked.

Though perhaps slower than before, the drumbeat of retail closures continues nationwide. Bed Bath & Beyond began the year with a round of closures, and even online retail behemoth Amazon is closing some of its physical stores in the U.S. and UK.

Some investors are retreating from retail. Early this month, mall giant Unibail-Rodamco-Westfield decided to sell its U.S. retail assets, which it acquired only about four years ago. The company holds 34 U.S. properties, including 24 standalone malls and 10 retail assets in airports.

On the other hand, a number of brands operating in the retail space are expanding. Dave & Buster's Entertainment, which operates 145 locations, is buying rival Main Event for $835M and plans "aggressive expansion."

The Howard Hughes Corp. has acquired a minority stake in Jean-Georges Restaurants for $55M, and it, too, is planning to expand the brand. Foxtrot, an upmarket convenience store with a combination of e-commerce and physical stores, is planning more physical stores in additional markets.