An interesting spread is certainly ZCN21-ZCZ21, that is, the spread built by buying the corn futures with delivery in July 2021 and selling the corn futures with delivery in December 2021. A calendar spread David CarliI am a macroeconomic and financial analyst with over 30 years’ experience, including two years as a fund manager. I specialise in currencies and commodities, and I am the author of several successful books on trading, macroeconomics, and financial markets.