Depending on the region involved, cars can be a luxury or a necessity. A survey among Americans reveal that a car is a necessity since the cost benefit of time involved in commuting using public transport is low. In the suburbs of The United States or Canada, owning a luxury such as a personal vehicle surpasses the benefit of using cheap public transport to get from point A to point B which takes a long time. Thus a luxury turns into a necessity because an efficient alternative that outweigh cost is not present. However in huge metropolitan areas such as Chicago, New York, Paris or Tokyo, the cost benefit of owning a car is less than the cost benefit of using public transport. Because mass transport is more efficient in huge cities, owning a car turns into a luxury because the operating cost to own one is higher than the cost of commuting using public transport.