23 CFR § 490.707
National performance management measures for traffic congestion
May 21, 2020
There are two performance measures to assess traffic congestion for the purpose of carrying out the CMAQ program (referred to collectively as the CMAQ Traffic Congestion measures. They are:
(a) Annual Hours of Peak Hour Excessive Delay (PHED) Per Capita (referred to as the PHED measure); and
(b) Percent of Non-SOV Travel.