The demand curve<span> usually </span>slopes<span> downwards from left to right; that is, it </span>has<span> a negative association (for two theoretical exceptions, see Veblen good and Giffen good). The negative </span>slope<span> is often referred to as the "law of </span>demand<span>", which means people will buy more of a service, product, or resource as its price falls.</span>
