This paper re-evaluates monetary measurement, specifically examining how currency equivalent aggregates provide new evidence on the important roles of money and the need to include money in models.

We develop a model of consumer choice with dynamic pricing and valuation uncertainty, and allow for purchase delay. Simulating the model, we find that delay is less likely when the expected increase in price is relatively large, even with high uncertainty. Using novel data that include information on trip characteristics, passenger demographics, fares, and timing of purchases from the Survey of International Air Travelers, we document delay patterns and price heterogeneity in the airline industry. We then perform a series of empirical tests to study selection into an arrival date, the propensity to delay, and the consequences of delay. Although trip and passenger characteristics drive much of the arrival behavior, the evolution of prices plays a role in the choice to delay. Consistent with our model, consumers in flight segments with relatively steep price paths are less likely to delay. Finally, controlling for trip and passenger characteristics and the purchase period, passengers who delay pay slightly more on average, though this effect disappears if we consider longer delay periods. This may suggest that consumers are willing to delay and pay more in order to reduce their uncertainty, but that they are unwilling to delay long periods of time if prices continue to increase.