On Thursday, United Parcel Service (UPS) predicted downbeat 2025 revenue as it cut back servicewith its largest customer, Amazon, in order to focus on more profitable businesses. The decision will cut Amazons transported volumes by more than 50% by the second half of 2026.The unexpected announcement came with disappointing revenue results, with UPS failing to meet expectations for 2024. UPSs Q4 revenue was $25.3 billion, slightly below the predicted $25.42 billion.This decision came at a time when UPS is struggling due to a decline in parcel demand following the e-commerce boom of the pandemic and an increase in shipments from discount online retailers such as Shein and Temu.UPS stock was down more than 14% as of Thursday afternoon, after falling during premarket trading. The decline was on track to break the current record for the stocks worst day, which occurred in July 2024, as MarketWatch reports.Shares have lost half their value since 2022, though the company said that carrying less freight for Amazon will eventually boost its revenue per piece.Amazon is our largest customer, but its not our most profitable customer, CEO Carol Tom told investors on a conference call Thursday.Foundational changesAmazon and its affiliates represented about 12% of UPS revenue in 2023, which is nearly all of its United States package business.The package carrier is hoping to gain volume from more profitable segments, such as healthcare-product shippers, small- and-medium-size businesses, and international markets.UPS expects revenue of about $89 billion for 2025, down from $91.1 billion in 2024. The parcel service has brought all of its UPS SurePost products in-house and will launch multiyear efficiency reimagine initiatives to drive about $1 billion in savings by rethinking its business design.The company aims to cut costs by closing buildings, reducing the size of its vehicle and aircraft fleets, and decreasing the size of its workforce.We are making business and operational changes that, along with the foundational changes weve already made, will put us further down the path to becoming a more profitable, agile, and differentiated UPS that is growing in the best parts of the market, said Tom in the annual earnings report.In 2025, UPS expects average daily U.S volume to drop about 8.5% year-over-year while revenue per package is projected to increase by 6%.