The international sustainable transport community began 2016 with strong momentum stemming from two major United Nations (UN) agreements in 2015: the Paris Agreement for preventing catastrophic climate change and the Sustainable Development Goals (SDGs), which set the global development agenda to 2030. To help ensure that these frameworks and agreements are effective,
tools for setting targets and measuring progress must be created. The UN has started a process of developing globally-agreed indicators for the SDGs that would help do that. This paper attempts to develop a relatively simple methodology for setting targets for one of those proposed indicators, the number of kilometers of rapid transit per urban resident, also known as the RTR ratio. Rapid transit infrastructure requires significant planning and investment over the long term and this easy-to-use methodology could help plan the amount of infrastructure and investment needed to achieve the global goals for sustainable development and tackling climate change.