Developed countries increasingly have the capacity to produce more grain than can be absorbed in commercial markets. This is in part due to the more general problem of immobility of agricultural resources, in part to inconsistencies in agricultural policy objectives pursued by exporters and in the policy instruments used. Overcapacity is aggravated by technological advances which enable countries which previously imported grain to become new and competitive exporters. The adverse effects of weather on crops is a variable factor beyond control in all regions, although some suffer from a more permanent vulnerability which results in periodic crop failures. The basic overcapacity therefore continues to be accompanied by recurring short-term scarcities of an emergency nature.
About 50% of the 1,052 million hectares of cultivated land in the world is used in the production of cereals, which constitute 80% of man's intake of food calories.