Source: Texas Transport Institute.
- Demographic growth is a straightforward factor as the more people the more potential drivers and thus of vehicles.
- The increase in trip length as well as the number of trips often relates the changes in the urban spatial structure. Particularly, suburbanization involves longer trips.
- A decrease in vehicle occupancy is commonly linked with limited opportunities for car pooling and trip chaining.
- In view of limited alternatives or the low convenience of public transit, many will switch to driving. Switching to driving is also the outcome of rising standards of living where a larger segment of the population reach an income level where an automobile becomes affordable.