Price volatility in food markets: can stock building mitigate price fluctuations?

This article studies US corn price fluctuations in the past two decades. Price volatility is explained by volatility clustering, the influence of energy prices, corn stocks and global economic conditions. A multivariate GARCH specification that allows for exogenous variables in the conditional covariance model is estimated both parametrically and semiparametrically. Findings provide evidence of price volatility transmission between ethanol and corn markets. They also suggest that macroeconomic instability can increase corn price volatility. Finally, stock building is found to significantly reduce corn price fluctuations.