ABERDEEN - The U.S. Postal Service says its Dakotas District led the nation in the overnight delivery of first-class mail for the last quarter of 2007.

"We continually work to improve every aspect of our performance. So we're obviously pleased that our overnight delivery service tops the nation," said Clem Felchle, manager of the Dakotas District - which includes North Dakota, South Dakota and the northwest corner of Minnesota.

The district's overall on-time performance score was 98 percent for Oct. 1-Dec. 31, the USPS said in a release.

The district has more than 5,000 people working in 700-plus postal facilities who process and deliver an average of 4.6 million pieces of mail per day to more than 810,000 addresses.

"It's a pretty simple formula," says Kim Pritchard, district senior plant manager. "This score is the direct result of our employees' hard work and commitment to our customers."