IMPORT cargo volume through busiest container ports should climb through this summer, but will remain well-below the record-setting levels seen during the pandemic, according to the National Retail Federation.

"Last spring and summer were the busiest ever as consumers spent freely and retailers brought in merchandise to meet demand," said federation vice president Jonathan Gold. "This year won't repeat that, but should be considered what was normal before the pandemic."

The federation's Global Port Tracker report shows major US container ports handled 1.55 million TEU of imports in February, down 14.4 per cent from January and down 26.8 per cent year on year. February was the latest month for which final numbers are available.

February is historically the slowest month of the year, but the number was the lowest since May 2020, when many factories in Asia and most US stores were closed due to Covid.

Ports have not yet reported March numbers, but Global Port Tracker projected the month at 1.68 million TEU, down 28.2 per cent year on year.

The report estimates that April is forecast at 1.86 million TEU, down 18 per cent from last year, May at 1.91 million TEU, down 20.1 per cent, June at 1.99 million TEU, down 11.8 per cent, July at 2.1 million TEU, down 3.9 per cent, and August at 2.13 million TEU, down 5.9 per cent.

Larger-than-normal year-on-year declines this year are skewed by unusually high volumes last year, particularly in the first half. Starting in 2021, a 20-month streak of imports above two million TEU compares to average imports of 1.8 million TEU per month pre-pandemic in 2019.

US container imports peaked at an all-time monthly record of 2.4 million TEU in May 2022 before falling below two million TEU in November 2022.

Mr Gold said the priority at the moment is resolving labour negotiations at the west coast ports that could create "self-inflicted supply chain challenges".

The federation sent a letter signed by 238 national, state and local trade associations to US President Joe Biden encouraging further engagement by the administration in the west coast talks.

Federation president and CEO Matt Shay also met with Port of Los Angeles executive director Gene Seroka to hear the latest developments regarding the status of negotiations.

While workers remain on the job, many shippers have shifted cargo elsewhere to avoid disruption.

"Compared with last year, the flow of import containers on the west coast continues to decline along with demand as carriers increasingly drop service to Los Angeles-area ports but stretch voyages to include other ports of call to help absorb excess capacity," said Ben Hackett, founder of Hackett Associates which produces the Global Port Tracker.

"Meanwhile, freight rates have been impacted by the fall in demand, but new ships are starting to show up and more have been ordered - a sign that carriers expect demand will improve by the time the new vessels are delivered."

Global Port Tracker shows the first half of 2023 is forecast at 10.8 million TEU, down 20.2 per cent from the first half of 2022. Imports for all of 2022 totaled 25.5 million TEU, down 1.2 per cent from the annual record of 25.8 million TEU set in 2021.

Global Port Tracker covers the ports of Los Angeles/Long Beach, Oakland, Seattle, and Tacoma on the west coast, and New York/New Jersey, Port of Virginia, Charleston, Savannah, Port Everglades, Miami and Houston.