Source: Millennium Cities Database for Sustainable Transport.
The strong association between density (number of people per hectare) and car use (share of car use for commuting) indicates that modal preference, urban form, and density are closely related. For Houston and Los Angeles, dispersed developments and low densities leave limited choices other than car usage, denser locations such as Paris and London have many more alternatives. The challenge of many cities wishing to address car dependency is to offer development plans that meet the mobility demands of their populations while increasing density.