In transport economics,[1] the value of time is the opportunity cost of the time that a traveler spends on their journey. In essence, this makes it the amount that a traveler would be willing to pay in order to save time, or the amount they would accept as compensation for lost time.
One of the main justifications [citation needed] for transport improvements is the amount of time that travelers will save. Using a set of values of time, the economic benefits of a transport project can be quantified in order to compare them to the costs (thus forming the basis of cost-benefit analysis). In particular, savings (or, for that matter, increases) in travel time form part of the change in consumer surplus for a transport project.