The national scanning score was 96.59 percent during the week ending May 22, a slight increase from one week earlier.
For the second consecutive week, Capital Metro led the areas with 97.04 percent, while Portland topped the districts with 98.05 percent.
Southern (96.74 percent) was second among the areas, followed by Great Lakes (96.68 percent).
Greater Boston (97.68 percent) climbed four spots to finish second among the districts, followed by Northern New England (97.66 percent).
Scanning allows customers to track their packages and other mail. It also helps the Postal Service improve efficiency and network management.
Informational videos about scanning are available at USPS-TV.