WASHINGTON — The U.S. Postal Service said Friday it lost $5 billion over the past year, and postal officials again urged Congress to pass legislation to help the beleaguered agency.

The agency’s seventh straight annual loss came despite its first growth in revenue since 2008. Operating revenue rose 1.2 percent to $66 billion, thanks to growth in the post office’s package delivery business.

But that was not enough to offset long-term losses in first class mail where revenues slid by 2.4 percent.

“We’ve achieved some excellent results for the year in terms of innovations, revenue gains and cost reductions, but without major legislative changes, we cannot overcome the limitations of our inflexible business model,” Postmaster General Patrick Donahoe said.