Imports at the nation’s major retail container ports are expected to be up 3.2% this month over the same time last year as stores bring in the last of the merchandise for the holiday season, according to the monthly Global Port Tracker report produced by the National Retail Federation and Hackett Associates.

“There’s still shopping to be done, and retailers are making sure the gifts that need to be under a tree are waiting on the shelves,” says Jonathan Gold, NRF’s vice president for supply chain and customs policy. “Imports are up a healthy amount over this time last year, and that’s a good sign for holiday sales and the economy.”

Ports covered by Global Port Tracker handled 1.67 million twenty-foot equivalent units in October, the latest month for which after-the-fact numbers are available. That was up 4.6% from September and up 7.4% from October 2015. One TEU is one 20-foot-long cargo container or its equivalent.

November was estimated at 1.53 million TEUs, up 3.6% from last year, and December is forecast at 1.48 million TEUs, up 3.2%.

The numbers come as NRF is forecasting $655.8 billion in holiday sales, a 3.6% increase over last year. Cargo volume does not correlate directly to sales because only the number of containers is counted, not the value of the cargo inside. But it nonetheless serves as a barometer of retailers’ expectations.

Cargo volume for 2016 is expected to total 18.6 million TEUs, up 2% from last year. Total volume for 2015 was 18.2 million TEUs, up 5.4% from 2014. The first half of 2016 totaled 9 million TEUs, up 1.6% from the same period in 2015.

January 2017 is forecast at 1.54 million TEUs, up 3.2% from January 2016; February at 1.49 million TEUs, down 3.5% from last year; March at 1.38 million TEUs, up 4.4% from last year, and April at 1.54 million TEUs, up 6.4%.

With cargo growth at covered U.S. ports for the year coming in at only 2%, Ben Hackett, founder of consulting firm Hackett Associates, says a trend of imports exceeding growth of gross domestic product appears to have ended.

“This is a new phenomenon,” Hackett says. “It was not long ago when industry leaders were doing their forecasts based on trade growth outpacing GDP by a ratio of more than 2-to-1. Those days are gone.”

Global Port Tracker, which is produced for NRF by Hackett Associates, covers the U.S. ports of Los Angeles/Long Beach, Oakland, Seattle and Tacoma on the West Coast; New York/New Jersey, Hampton Roads, Charleston, Savannah, Port Everglades and Miami on the East Coast, and Houston on the Gulf Coast.