In 1980, 33.6% of Iowa corn was fed to Iowa livestock and poultry with 8.6% being used for non-ethanol corn products, 0.6% for ethanol, 10.4% was shipped to other states (mostly for feed use), 26.9% was exported to international markets, and 19.8% was held as ending stocks.

By 2023, those percentages had changed a lot. The latest estimates are that 21.0% of Iowa corn is used for feeding Iowa livestock and poultry, 7.8% is used for non-ethanol processing, 58.2% is used for ethanol, 3.7% of Iowa’s corn use now comes from other states, 6.5% moves to international export markets, and 10.2% is held as “ending stocks. (Figure 1). In estimating these use categories, movement of corn into Iowa from other states was limited to 100 million bushels per year. If such inflows are left unrestricted and exports are calculated as Iowa’s percent of national production, then inflows of corn to Iowa from other states would have...