The U.S. Postal Service announced Tuesday that it swung to a fiscal first-quarter loss as expenses increased while revenue fell, as shipping and packages volume declined during the holiday period. For the quarter to Dec. 31, the Post Office recorded a net loss of $1.55 billion, after net income of $318 million in the same period a year ago. The "controllable" loss, which excludes items out of management control, such as unfunded liability expenses, was $195 million, after income of $727 million a year ago. Revenue fell 0.9% to $21.29 billion as volume declined 4.1% to 35.09 billion pieces. First-class mail revenue rose 2.5% to $6.46 billion and market mail revenue increased 7.3% to $4.47 billion, but shipping and packages revenue dropped 7.9% to $8.64 billion. Meanwhile, total operating expenses increased 7.9% to $22.82 billion. "Despite the record package volume during the holiday season, the overall surge in e-commerce has begun to subside," said Chief Financial Officer Joseph Corbett. "This shift in market trends, along with the continued declines in mail volumes, our increasing costs, and general economic conditions creating inflationary pressure, highlight the ongoing financial challenges that the Postal Service faces."