In a market economy, price changes are determined by the interaction of supply and demand. Supply and demand is also known as fundamental analysis. In this tutorial, you'll learn how to estimate market price for a commodity using the basic law of supply and demand as reflected in the stocks-to-use ratio. Stocks-to-use ratio is data in establishing asking prices for commodities. In order to better understand fundamental analysis, you must first have working knowledge of the economic theory of supply and demand. Supply and demand graphs are broker provided to further illustrate this concept.