Macy’s plans to close about 100 stores nationwide in response to a trend of declining sales.

The Cincinnati-based retailer broke the news Thursday in a media release that accompanied its second-quarter earnings report. One hundred stores comprise about 14 percent of the entire chain, which consists of 728 locations, including 675 larger “full-line” stores and 53 smaller stores. The company said it has not yet decided which locations will be closed.

“Most of these stores will close early in 2017, with the balance closing as leases and certain operating covenants expire or are amended or waived,” the release said. “In a number of cases, stores will be closed as the value of the real estate exceeds their value to Macy’s as a retail store. The locations of the 100 stores to be closed will be announced at a later date, once the company makes final decisions.”

According to its website, Macy’s employs about 300 workers at its two Maine locations in South Portland and Bangor.

Macy’s said nearly all of the stores to be closed are currently making money, but that their sales volume and profitability in most cases have been declining steadily in recent years.

The company said it recognizes that those locations aren’t yielding an adequate return on investment, and that they often “do not represent a customer shopping experience that reflects our aspirations for the Macy’s brand.”

“We decided to close a larger number of stores proactively so we can invest in a winning customer experience in our most productive and highest-potential locations, as well as invest in growth sooner and more aggressively in digital and mobile,” it said.

Macy’s said the 100 store closures will result in a reduction in total sales of about $1 billion, but it said those losses will be offset by even greater reductions in expenses.

The company said it will communicate its store closing decisions directly with the employees in the affected locations before making a public announcement.

“Macy’s is committed to treating associates affected by store closings with respect and openness,” it said. “Associates displaced by store closings may be offered positions in nearby stores where possible. Eligible full-time and part-time associates who are laid off due to the store closing will be offered severance benefits.”

Macy’s said it will invest in improvements at the stores that remain open. It said it plans to add new vendor shops inside each location, bring new businesses onto the sales floors through additional license agreements, increase the size and quality of staffing through programs such as My Stylist personal shopping services, incorporate new technology into each store, accentuate high-potential businesses such as fine jewelry, and create new in-store events and experiences.

The closures won’t be the first for Macy’s in recent years. Since 2010, it has shut down roughly 90 locations, and 13 new Macy’s stores have been opened. In addition, six Macy’s Backstage outlet stores opened in fall 2015.

Also Thursday, the company reported second-quarter net sales of $5.87 billion, down slightly from $6.1 billion in the second quarter of 2015. Its operating income was $372 million before writing down $255 million in impairments, settlement charges and other costs related to the upcoming store closures. In the second quarter of 2015, operating income was $436 million.