Approaches to Forecasting Third Performance Management Rulemaking (PM3) Measures for Target Setting
This document offers a step-by-step calculation guide for three forecasting methods in support of target setting for the Third Performance Management Rulemaking PM3 travel time-based performance measures.1
The three forecasting methods covered in this document are:
- Extrapolation of past trends (macroscopic).
- Highway segments “at risk” for unreliability (microscopic; based on identifying segments that close to the reliability threshold).
- Model-based forecasting.
The methods described herein provide technical information on which targets can be determined, but ultimately state departments of transportation (DOT) and metroplitan planning organizations (MPO) select final targets using a consensus-based process. Many factors outside of the technical information provided by these methods should be considered in target setting. Among them are funding availability and agency priorities across all program areas.