DALLAS (AP) - Facing an even bigger mountain of packages this holiday season, FedEx and UPS are hiring more workers to avoid the delays that frustrated shoppers and gift recipients a year ago.

Last December, the delivery giants were caught off-guard by bad weather and a surge in last-minute online shopping. An estimated 2 million packages were late at Christmas.On Wednesday, FedEx Corp. said it expects deliveries between Thanksgiving and Christmas Eve to rise 8.8 percent over last year, to 290 million shipments. Volume is expected to surge on each of the first three Mondays in December, with FedEx predicting a peak of 22.6 million shipments on Monday, Dec. 15.The delivery companies and Internet retailers are benefiting from a strengthening economy and optimism about consumer spending. At the same time, they're dealing with consumers who increasingly enjoy the ease of shopping on computers and mobile devices but expect the goods to show up almost as quickly as if they had shopped at a store. That expectation is often fed by online retailers, who hold out the promise of free delivery until right before Christmas.About 1.3 million express packages handled by UPS and 618,000 carried by FedEx failed to get delivered on time last Christmas Eve, according to ShipMatrix Inc., which makes software for shipment tracking. The firm's president, Satish Jindel, said UPS and FedEx were at fault only 30 percent of the time.In most cases, retailers promised guaranteed express delivery but tried to save money and didn't pay the delivery companies for that speedier service, Jindel said.The merchants face tough competition for consumers who base purchases first on price, and second on free shipping, and the faster the better.