Assessing the operational performance of traffic signals required detailed information regarding sensors inputs and controller actions. In 2012, a series of enumerations used to encode traffic signal events at a 100 millisecond was developed and published at https://doi.org/10.4231/K4RN35SH. Techniques for using that data are published in https://doi.org/10.5703/1288284315333 and https://doi.org/10.5703/1288284316063
As part of a multi-state Federal Highway Administration pooled fund study, TPF-5(377), a series of stakeholder engagements and panel meetings were conducted in 2018 and 2019 to update these enumerations. In 2020, updates to the enumerations included minor changes to event codes 14, 17, and 54
