DES MOINES, Iowa (AP) — One of the new laws enacted this month allows an increase in the Iowa Corn Checkoff. It’s money collected from each bushel of corn sold to promote the grain. Checkoff funds have been used to promote ethanol, such as sponsoring an Indy Car race. The checkoff can only be increased after farmers approve it in a referendum.

The first authorization on the checkoff in 1977 set a maximum of 1 cent per bushel sold. In 2012 corn producers approved that amount, which meant state legislators had to update the law for the checkoff to go any higher. Corn promotion officials say they have no plans to increase the checkoff, which generates as much as $20 million a year.