Intermodal freight volumes posted a fourth quarter growth rate of 5.8% year-over-year, but most of it came from international movements.

International volume was up by 7.7%; domestic container taffic grew by a modest 2.5% but piggyback trailer loads rose by 12.2%.

The numbers come from the Intermodal Association of North America’s 2017 fourth quarter and year-end Intermodal Market Trends & Statistics report.

“Intermodal delivered in 2017, thanks in large part to growth on the international side,” observed Joni Casey, president of IANA. “The imbalance between imports and international volumes during 2016 has reversed, resulting in a strong 4.7% volume gain for the year.”

In this fourth quarter, the seven highest-density trade corridors accounted for 62.0% of total volume and were up collectively 3.7%.

The Eastern-Western Canada corridor expanded by 12.7%, exceeding all other lanes by a wide margin. Two other lanes, the Northeast-Midwest and the South Central-Southwest, reached 5.0% growth.

The Midwest-Southwest, intra-Southeast and Southeast-Southwest lanes recorded growth of 2.4%, 2.2% and 1.0%, respectively. The Midwest-Northwest corridor volume shrank 5.2%, the only lane reflecting a decrease in volume.

Traffic generated by third-party intermodal marketing companies (IMCs) increased 16.8% year-over-year in Q4, with almost all of that gain taking place in the highway segment.

This is the second consecutive quarter when both intermodal and highway loadings increased, For the full year, IMC volumes were up 5.4%, with highway moves growing at about twice the pace of intermodal loadings.