Field crops operate on an annual supply schedule and a variable demand schedule. Though the production of these commodities has become a world operation during the last ten to twenty years, the bulk of the supply is usually available at the time of harvest for the major producing regions. Demand, on the other hand, is fairly evenly spread throughout the year, though certain periods, such as the spring and early summer, tend to see increase grain demand. This sets up a unique feature in the market where price acts as a rationing device for annually produced commodities, as consumers and producers cycle through being gripped by the forces of fear and greed.

When a market has annual production, or supply is replenished once a year, this supply must be rationed or spread out over the rest of the year. The market mechanism for rationing supply is price. When prices are high, consumers are discouraged from consumption to some degree and the supply will last longer. When prices are low, consumers are encouraged to use the product to a certain extent and the supply is used up. But price also acts as a stimulus for supply. When prices are high, producers are encouraged to increase production to increase profits. However, when prices are low, producers tend to decrease production since profit margins are not as great. This type of market behavior sets up a paradox, in which low prices discourage production, and high prices encourage production, but producer reactions to prices cannot occur until the following year. As such, swings in annually produced commodities, especially when supplies are currently tight, tend to be exaggerated when the crop is vulnerable to damage.

The exaggerations of price are often referred to as building a "risk premium" into the crop. Since price will ultimately ration the supply that when a crop is feared to be in limited supply prices tend to rise to spread out supply. Annually produced commodities tend to go through cycles of building risk premium and destroying risk premium as the crop goes through its various stages of production. Risk premiums are built when consumer's fear limited supply and producers have an economic motive to with hold supply from the market place. So during potentially tight supply times, consumers tend to pay higher prices for fear of not being able secure supply, while producers must be encouraged to sell at these higher prices to satisfy their profit motive, or greed.

However, as the consumers meet their current demand needs they tend to be motivated to find alternate sources of supply or will use other products in substitution (greed) while producers fear missing the higher prices and tend to open the flood gates of supply. As such, when the crop is in danger of potential damage, fear grips the consumer and greed the producer. Prices then rise as the market place builds the risk premium into the crop to ensure supply at a later date.

As can be clearly seen, field crops tend to rise going into planting. All of the commodities in question tend to increase in value, as the market-place begins to appreciate all that can go wrong with the coming crop. After all, nothing can grow with out first being planted, so planting must go smoothly for the crop to develop to its full potential. Hence, since this is the first step the production of grains, it is the point when the crop is the most vulnerable to damage, and hence prices tend to factor in a "risk premium" to help ensure that grain is rationed throughout the year.

As can be clearly seen in the above table, Grain futures tend to rally going into pollination. However, as this milestone is crossed and supply becomes more certain, prices fall.

Again, it is clear that the market has historically rallied going into harvest and harvest preparation, as the marketplace increases the price to discount the likelihood of yield diminishing delays in the crop.

As is clearly seen in the data above, the building of the "risk premium" during the planting, pollination, and harvest segments of grain production clearly demonstrates the old traders adage.