Why such surprise about the corn crop? - TwinCities.com

Why such surprise about the corn crop? - TwinCities.com:The article begins with a discussion of Eugene Fama and market efficiency--the reaction to new information:"One also wonders why corn prices jumped more than 20 percent. The new information was not about a crop-destroying tsunami or a sudden attack by UFOs. The raw information about the weather and its impact had been out there for weeks.