UPS Inc., the world's largest shipping carrier, expects to deliver roughly 22 million small packages on its busiest day this year _ projected to be Dec. 21.
UPS, based in Atlanta, said Monday that's about a 40 percent increase over normal daily delivery volumes.
It says that for the entire holiday season, stretching from Thanksgiving to Christmas, it expects to deliver roughly 400 million packages around the world, up slightly compared to the 2008 holiday season.
Peak projections from UPS and rival FedEx Corp. are closely watched because they are an indicator of how well the economy, especially in the retail sector, is doing.
UPS did not make a peak projection last year and did not say how many packages it delivered on its busiest day.
UPS expects to hire around 50,000 seasonal workers to help with the extra volume this holiday season.
UPS said people can ship items by air as late as Dec. 23 for delivery on Christmas Eve, Dec. 24.
UPS' peak projection consists of small package volume handled by UPS to the point of delivery.
FedEx, based in Memphis, Tenn., said last week that it expects to ship 13 million packages on Dec. 14, which it expects to be its busiest day this year.
That would be up more than 8 percent from about 12 million packages shipped on its peak day last year.
FedEx numbers include a partnership with the U.S. Postal Service, in which FedEx picks up or accepts shipments and delivers the packages to a post office for final delivery by a postal carrier.
Dec. 17 is the last day to guarantee delivery before Christmas through FedEx Ground. Dec. 23 is the last day to ship by way of the company's Express service.