Mail service deteriorated “in a very public way” after USPS lowered its service standards and carried out equipment and plant consolidations and other operational changes in response to falling volume, an IG report said.

USPS revised its first-class mail standards in January 2015, effectively eliminating single-piece overnight first-class mail service and shifting mail from a two-day to a three-day service standard. These changes allowed the Postal Service to process mail on fewer machines and thus reduce the space it needed, but soon “individual customers, commercial mailers, and members of Congress all complained.”

Delayed mail processing increased nationwide by 51 percent compared to the same period in 2014, while two-day and three-day first-class mail weekly scores declined by as much as 7 percent and 34 percent, respectively.

What’s more, management could firmly demonstrate that it achieved only 10 percent of the annual savings of over $805 million it had projected from making those changes.

The report recommended that USPS implement a nationwide strategy to improve mail processing productivity before it makes more nationwide operational changes or consolidations.