A late 2014 harvest and strong incentive to store corn has created an early season U.S. corn deficit, according to a new report by the Rabobank Food & Agribusiness Research and Advisory group.

The report, titled “Waiting for the Record U.S. Harvest to Flow,” said physical inventories of corn and soybeans have been slow to accumulate despite projections of record harvests for both commodities.

“As the lethargic grain flow continued into...