The U.S. Agriculture Department's comment period ends on Thursday on whether to release weekly export data for dried distillers' grains, a "co-product" of ethanol production that has become increasingly popular as animal feed.
The government currently releases monthly export data for so-called DDGs and the decision on weekly numbers could come within months, said USDA spokeswoman Sally Klusaritz.
Ethanol producers and traders are divided on a weekly release for DDGs - a more frequent dataset would provide more visibility in the billion-dollar market, but a report showing large volume of weekly sales could lead to a spike in prices.
Bill Day, a spokesman at leading ethanol maker Valero Energy Corp, said the company is in favor of weekly data.
"It makes sense to Valero, as a producer of DDGs, that they would be subject to the same kind of weekly data reporting that other commodities are," Day said.
The sale of DDGs, to foreign and domestic buyers, makes up about 20 percent of the profit margin for ethanol makers such as Valero, Archer Daniels Midland Co and POET Biorefining, industry experts said.
"It's make or break. Forty percent of the corn crop goes to ethanol and a third comes out as DDGs, so that's 13 percent of the corn crop ending up as DDGs," said Wally Tyner, an energy economist at Purdue University in West Lafayette, Indiana.
"The problem with weekly numbers is that they are weekly - you might have a lot of transactions this week, but not much next week."
The ethanol industry's lobbying arm, the Renewable Fuels Association, is opposed to a weekly dataset, according to RFA vice president of research Geoff Cooper.
"We think it's unnecessary," Cooper said. "It's one more administrative burden and there's no clear benefit."
The USDA proposed weekly export data for DDGs last June, ending a comment period in August before extending the comment period in March until 11:59 p.m. EST (0459 GMT) on Thursday.
The agency already releases weekly exports on agriculture products ranging from corn to soybeans to beef.
The USDA also proposed weekly pork export data at the same time it initially proposed DDGs. The agency started releasing pork data three weeks ago, six months after ending the comment period.
DDGs exports in February, the most recently available monthly data, totaled 617,894 tonnes, up 5.6 percent from January and the largest sales since October. China is the top export destination, followed by Mexico and Canada.
The USDA projects 32.5 million tonnes of DDGs will be produced this year - triple the output eight years ago - all of which will be consumed domestically or abroad. Exports are estimated at 6.9 million tonnes, down from 7.5 million tonnes last year and the smallest since the 2008/09 marketing season that runs Sept. 1 to Aug. 31.
Production of the animal feed declined after ethanol plants reduced operations when last summer's worst drought since 1934 sent corn prices to a record high and squeezed profits.