An urban mobility index for evaluating and reducing private motorized trips

•We proposed a new practical urban mobility index (UMI).•This UMI rates urban mobility variables.•This UMI creates a foundation for evaluating urban mobility at the city level.•This method can be utilized for cities around the world.•This UMI method presents improvements toward achieving sustainable urban transport.

Modern cities seek policies to sustain their urban mobility by reducing car externalities. To maintain sustainability, urban designers and planners should consider different social, economic, and environmental indicators. Currently, efforts are being made to evaluate the relationship between urban structure and car usage. However, few studies have been conducted to evaluate private motorized trips at the macro-level. This study attempts to create a foundation for evaluating private motorized trips at the city level by introducing an urban mobility index (UMI). UMI is a measure for evaluating transportation in cities at the macro-level. This research presents urban mobility indicators that are correlated to a percentage of daily trips made through private motorized modes in order to calculate UMI. An analytical point system comparing existing cities to the best existing value is proposed in order to estimate this UMI. This research employs the International Association of Public Transport (UITP) as a database. Although this method can be utilized for cities worldwide, this research uses it to assess Hong Kong and Chicago. This method can identify existing problems and can be used to propose solutions for reducing car usage.