when demand is elastic and trips arc generated when demand is elastic and there is a shift in the demand curve (due to increased demand even at the same price), the increase in user benefits (Consists of Areas A and B in Figure 4.4) but Area B is due only in part from the improvement. The changes in user benefits for the scenarios discussed above are in response to changes within the transportation system itself, such as nature of demand elasticity, changes in demand (induced or generated), or changes in supply (trip delays, travel times, price). The figures can also help explain the effect of exogenous changes, which include :