An employee at the Utah County Election office handles mail in ballots in the midterm elections on November 6, 2018 in Provo, Utah. (Photo by George Frey/Getty Images)
Mailing in your ballot? Here's how it works
01:48 - Source: CNN
CNN  — 

As states begin to mail ballots to voters, on-time delivery of first-class mail is plummeting across the US, according to new Postal Service documents submitted to a federal court.

The USPS documents show first-class mail’s on-time delivery performance for the week of September 19 sank to 84.23%, a decline of 4.51 percentage over two weeks. That means the nationwide on-time delivery score for first class mail are nearing lows seen in July and August, when the agency experienced significant delays because of significant changes to postal operations.

The on-time delivery of first-class mail has taken on even greater significance in October because election mail, like ballots, are handled as first-class mail.

Of the 28 states that are sending ballots to voters, 43% of them are seeing the worst on-time delivery of first-class mail so far this year. All but two of those the states have seen their first-class mail’s on-time delivery drop over the last two weeks.

The USPS blamed a portion of the drop in the last week to issues at the Great Lakes and Chicago Surface Transfer Center, but did not elaborate on what the problem was.

“To address this issue, support teams have been on site and are working with contracting teams to increase staffing and reduce cycle times,” the postal service said in a statement.

The continued drop in on-time delivery threatens to undermine the USPS’ and embattled Postmaster General Louis DeJoy’s promises to Americans, Congress and to federal judges that the USPS will be able to handle the surge in mail from ballots.

Nationwide drop fueled by on-time delivery collapse in eastern US

Six of the seven USPS regional areas are seeing a drop in their on-time score for first class mail delivery. The nationwide drop is due largely to a profound and region-wide collapse of on-time first-class mail delivery in the eastern United States.

Although first-class mail on-time performance scores are cratering, the nationwide on-time delivery scores for marketing mail and periodicals increased from mid-July and early August. Periodicals are now delivered on-time 79.72% of the time, up from under 70% in early August. Marketing mail is on-time 88.68% of the time, up from 81% in early August.

The USPS did not respond to CNN’s inquiries as to why only first-class mail on-time delivery had decreased.

CNN’s Kristen Holmes contributed to this report.