The latest report estimates corn use for ethanol this year to total 5.25 billion bushels while total corn supply is expected to reach 15.47 billion bushels.

But since 18 lbs of a 56 lbs bushel of corn is returned as dried distillers grains (DDGs), the actual amount used for ethanol is some 67 percent of a bushel, which in turn means the corn that will be used this year for ethanol is actually 3.51 billion bushels which is 22 percent of the total supply of corn.

In fact, based on the latest report, the volume of corn used for ethanol production in relation to the total corn supply is slightly lower in 2014/15 than it was a year earlier. In the 2013/14 year, the volume was 23 percent of the total supply (the reason being overall corn supply is higher this year).

The numbers above once again disproves age-old allegations that more corn is used for ethanol instead of food. So the next time you hear someone bring up the "Food vs Fuel" theory, send them to the USDA's website and let them do the math.