Source: Adapted from Toronto Board of Trade (2014) Toronto as a Global City: Scorecard on Prosperity – 2014. Toronto: Toronto Board of Trade.
Communing is an important component of urban mobility since it accounts for a large share of urban movements and substantially impacts the commuters’ welfare. The time spent commuting has remained relatively constant throughout history, with about 60 minutes per day (30 minutes in each direction). This is known as Marchetti’s constant, in the name of the physicist who first established the relation. While the commuting time may remain constant, the commuting distance is more extensive due to improvements in urban mobility.
Because of high levels of motorization, American cities tend to have the lowest average commuting time in the world. The commuters of Europe and Japan have longer commuting times, mostly because they are more dependent on walking and public transit despite more compact cities. There is thus an inverse relationship between the level of public transit use and commuting time as passengers tend to spend more time waiting and transferring within the transit system. However, the last decade has shown growing commuting times, particularly in China, mainly due to increasing motorization in metropolitan areas and the related congestion. Shanghai is now one of the world’s cities having the longest commuting time.