NTD Sampling Manual
The NTD Sampling Manual is a guide for NTD reporters from urbanized areas that need to conduct data sampling to develop statistically-valid estimates of passenger miles traveled (PMT) and unlinked passenger miles (UPT) and report them to the NTD. FTA will accept estimates of PMT and UPT if the reporter follows the methodologies described in this Manual. FTA has withdrawn Circulars 2710.1A, 2710.2A, and 2710.4A as accepted sampling approaches and replaced them with the NTD Sampling Manual.