Rate levels on the major trade lanes out of Asia should be rising as peak season begins and key destination ports remain congested, but the spot market has continued to decline.

US retailers’ stockpiling of inventory has not only swelled the number of import boxes sitting on marine terminals and railheads, it has also left thousands of chassis idled with unopened containers on top of them at distribution centers around the country.

Global volume data shows a slowing of the container shipping market, and a new forecast does not expect any strengthening of demand this year.

South Korea’s shipowners’ association said penalties imposed by regulators would damage the country’s link to the global supply chain and lead large foreign carriers to avoid South Korean ports.