American wheat shipments dropped to the lowest ever, hampered by a shrinking Mississippi River and competition from ample global grain supplies.

Drought has dried up the Mississippi, where roughly two-thirds of US grain exports historically have been shipped on barges to the US Gulf. Water levels have improved slightly from last month’s record low, but the world’s crop buyers have already been purchasing more supplies from elsewhere. That’s limited demand for US grain and contributed to the country losing its status as the shipper of choice.

Read More: Twilight of an Agripower: How US Lost Powerful Statecraft Tool

Export inspections of American wheat in the week ended Nov. 2 totaled only 71,608 metric tons, with some wheat shipped from Duluth, Minnesota, through the Great Lakes but virtually nothing on the Mississippi River, according to the US Department of Agriculture. That is the smallest total on record in weekly USDA data going back to 1983.

(Corrects story and chart to show lowest shipments ever in data going back to 1983)