Whole Foods Market stores are facing an inventory problem that has led to empty shelves, according to a report.

Employees of Austin, Texas-based Whole Foods are blaming the problem on a new buying system, order-to-shelf, that was implemented by the company in early 2017, according to a story on businessinsider.com.

Order-to-shelf preceded Amazon’s purchase of Whole Foods, according to the story. Under the system, employees largely bypass stock rooms and carry products directly from delivery trucks to store shelves. The aim is to cut costs, better manage inventory, reduce waste and clear out storage.

But order-to-shelf has also produced empty shelves and angry customers, according to Whole Foods employees interviewed for the story.

"At my store, we are constantly running out of products in every department, including mine," according to an assistant department manager of an Illinois Whole Foods quoted in the story. "Regional and upper store management know about this. We all know we are losing sales.”

Order-to-shelf has led to a dramatic reduction in back stock — products stored in stores’ back rooms until they are needed on store shelves — according to the story.