The U.S. Postal Service’s plan to end Saturday mail delivery this August is one of many hard choices ahead for the postal service as it struggles to deal with the $15.9 billion loss it posted last year.

The postal service is an odd institution — an independent agency that functions in many respects as a business, although Congress has a say about some aspects of its operations. That’s a challenging management structure for an agency that touches virtually every American with its work.

Postal officials said that limiting mail delivery to Monday through Friday could save the agency $2 billion a year. The delivery of packages, a growing part of the agency’s business, will continue on Saturdays, and post office boxes will continue to receive mail on Saturday.

The postal service has seen a dramatic drop in mail delivery as Americans pay more bills online and use email rather than letters to communicate. We must wonder if ending Saturday delivery will further erode the appeal of postal mail, creating a spiral of decline for mail delivery.

Taken alone, ending Saturday mail delivery won’t put the postal service in the black. The agency needs more comprehensive change — perhaps on the order of the revolution in management that brought the modern postal service into being in 1971.