Source: National Household Travel Survey, FHWA, 2001.
Main Purposes of Passenger Trips
Each trip is undertaken to satisfy a purpose and the nature of this purpose is illustrative of a very specific mobility context in terms of the time of the day and even to mode used. The above graph provides a breakdown of the main categories of travel by purpose in the United States. Since the majority of the population is urban, these distribution is reflective of the purpose of urban trips. Although different urban settings will have a different trip compositions, most of the trips undertaken in urban areas across the world are work-based:
  • Work. Commutes performed towards the workplace, which represents approximately 34% of daily commutes.
  • Business (work). Trips from the workplace to a business destination.
  • Business (personal). Trips related to personal activities such as restaurants.
  • Shopping. Commutes towards any store regardless of its size, merchandise, or whether or not any purchases are made. These commutes represent approximately 13% of all daily travel.
  • Recreational. Commutes performed with the intention of recreation such as a cultural or sport event. Similar to shopping, these represent about 12% of daily commutes.
  • Education. Commutes towards a learning establishment by those seeking any type of training, regardless of the level of learning. These commutes represent 3.5% of the daily travel total.
  • Social. Trips related to social activities such as visiting family or friends.
The accumulated total of commutes terminate at home since every commute involves a round trip back home. This is referred to as the symmetry assumption; any trip from home is usually accompanied by a corresponding return trip at the end of the day or given activity.