After a record-setting summer propelled by a rebounding global economy and efforts by retailers to import holiday goods early, seagoing import traffic will level off as 2017 ends with racks and shelves fully stocked up for the holiday shopping season, according to the monthly "Global Port Tracker" report released today by the National Retail Federation (NRF) and consulting firm Hackett Associates.

The 11 major U.S. container ports surveyed by NRF and Hackett set monthly records for twenty-foot equivalent unit (TEU) traffic in July and August. July set the highest volume totals in the survey's 17-year history, only to be surpassed a month later.

With most seagoing imports cleared into U.S. commerce or already on store shelves for the holidays, the import numbers will revert to seasonal trends and level off in the next couple of months. November import volume is forecast to be 1.63 million TEU—down 0.5 percent from last year—and December is forecast at 1.6 million TEU, up 2 percent from last year.

"Retailers have been bringing in merchandise since late summer, and supply is ready to meet the increased demand that has been building throughout the year," said Jonathan Gold, NRF's vice president for supply chain and customs policy, in a statement.

The ports handled 1.76 million TEUs in September, the latest month for which after-the-fact numbers were available, according to the report. This marked a 2.3-percent decrease from August, but was still a 10.5-percent increase year over year, according to the report.

Meanwhile, October volume at the ports was estimated at 1.75 million TEU, up 4.9 percent from last year. While not a record, those two months marked only the fifth and sixth times that monthly volumes have hit 1.7 million TEU or higher since NRF began tracking imports in 2000.

The Global Port Tracker study, which Hackett produces for NRF, covers the ports of Los Angeles/Long Beach and Oakland, Calif., and Seattle and Tacoma, Wash., on the West Coast; New York/New Jersey, Hampton Roads, Va., Charleston, S.C., Savannah, Ga., and Port Everglades and Miami, Fla., on the East Coast; and Houston on the Gulf Coast.