Corn prices fell a bit this week but have still risen 25% so far this month. High corn prices ripple through many sectors, but few as badly as food companies for which corn is a major input. Cereal companies and livestock companies are at the top of this list for those most affected by the newly expensive inputs. There aren't very many companies in this space Austin would recommend right now. Tough margins and sensitivity to commodity prices make them unattractive long-term investments.

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