Pourquoi les prix agricoles augmentent-ils ?

¹ Ancien directeur de recherche INRA ; Membre de l’Académie d’Agriculture, 3 quai Malaquais 75006 Paris
² CIRAD, 45bis avenue de la Belle Gabrielle, 94736 Nogent sur Marne
³ CIRAD, Université de Sao Paulo, Rua Ferreira Franca 40, Appdo 22A, Alto pinheiro, Sao Paulo, Bresil

^* boussard@ivry.inra.fr
^** francoise.gerard@cirad.fr
^*** piketty@cirad.fr

Abstract

Agricultural prices recently rocketed, calling for significant food price increase, and granting farmers large profits they did not claim. Such an increase in agricultural commodity prices were considered perfectly unrealistic a few years ago. Many explanations are now provided, involving drought in Australia, demand for biofuels, and consumer habits evolution in India or in China. Without denying any validity to such assertions, another hypothesis is proposed here, supported by the ID3 model by CIRAD: the recent price upsurge is only the logical consequence of expectation errors and the unstable character of the market equilibrium point. In this context, the deregulation of markets, particularly by the EC (complying with WTO requirements), which, till recently, was the ultimate stockpile operator, created a new situation likely to feed a chaotic cobweb. This implies that the high price episode will only be temporary, and followed by even more depressed prices. Yet, it might happen that the increased volatility leads to an average price higher than during the state involvement, contrary to policy makers expectations.