Conversely, as the price goes down, the product becomes a cheaper way
of satisfying a desire. Households will demand more of it as they
substitute away from other products whose prices have not fallen. For
example, if the price of tomatoes falls, many shoppers will buy more
tomatoes and less of other vegetables.
1 In this chapter we explore a product’s demand curve for the market as a whole—what we often
call the market demand curve. In Chapter 6 we discuss how this market demand curve is derived by
adding up, or aggregating, the demands of different individuals.