The U.S. Postal Service has faced scrutiny for making major operational changes in an election year when many more Americans are mailing their ballots because of the coronavirus pandemic. But new statistics show the USPS is doing a worse job of delivering the mail on time, raising concerns that some ballots may be delayed. The Postal Service said Friday that its on-time delivery rate for first-class mail slipped to 85.6% for the week ended October 16. That’s down from nearly 91% over a three-month period ending in June, noted Paul Steidler, senior fellow with the Lexington Institute, a public policy...