This is normal shipping stuff. In total, the port’s data shows, import volumes will be down 31 percent next week compared to the same week last year. “It’s unprecedented in the history of containerization.” The blank sailings, he says, are “an early canary in the coal mine. Right now, the US government has said that it is negotiating tariff levels with many countries, including China, so the container shipping picture could change quickly as deals are signed or dashed. Some of the blank sailings currently being recorded are happening because of economic uncertainty, says Jean-Paul Rodrigue, a professor of maritime business administration who studies port operations at the University of Texas A&M-Galveston.