"These numbers all show significant increases for the months when retailers will be bringing merchandise into the country for the crucial holiday season, and we're also expecting an increase for the full year," said Jonathan Gold, NRF vice president for supply chain and customs policy. "Actual sales will depend on how consumers react to employment levels and other indicators, but retailers are clearly stocking up and hoping for a stronger fall and winter than they saw last year."

U.S. ports followed by Global Port Tracker handled 1.41 million twenty-foot equivalent units in June, the latest month for which after-the-fact numbers are available. That was up 4.7 percent from May and 10.7 percent from June 2011. One TEU is one 20-foot cargo container or its equivalent.

July was estimated at 1.39 million TEUs, up 2.6 percent from last year. August is forecast at 1.44 million TEUs, up 6.3 percent; September at 1.46 million TEUs, up 7.3 percent; October at 1.47 million TEUs, up 13.2 percent; November at 1.3 million TEUs, up 2.4 percent; and December at 1.23 million TEUs, up 2.4 percent.

The first half of 2012 totaled 7.6 million TEUs, up 3.8 percent from the same period last year. For the full year, 2012 is expected to total 15.9 million TEUs, up 4.8 percent from 2011.

"Indicators are mixed, and analysts are getting nervous and expecting the U.S. consumer to retrench and reduce consumption," Hackett Associates founder Ben Hackett said. "But we continue to believe that trade will not weaken as much as expected by others."

Global Port Tracker, which is produced for NRF by the consulting firm Hackett Associates, covers the U.S. ports of Long Angeles/Long Beach, Oakland, Seattle and Tacoma on the West Coast; New York/New Jersey, Hampton Roads, Charleston, Savannah and Miami on the East Coast; and Houston on the Gulf Coast. The report is free to NRF retail members, and subscription information is available here or by calling (202) 783-7971. Subscription information for non-members can be found here.

Source: National Retail Federation