Procedures for Estimating Demographic Data for TRIPCAL5

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P.L. Ellis, G.B. Dresser

Publication Date:

September 1995


This manual was developed as part of a project funded by the Texas Department of Transportation (TxDOT) to implement methods of improving transportation planning techniques and is based on research conducted in a previous project to examine methods of improving transportation planning techniques. Within these research projects, the need to develop a set of simplified procedures for developing the input data for travel demand forecasting that can be used by small area Metropolitan Planning Organizations (MPOs) was identified. Many MPOs under 200,000 in population do not have the staff or financial resources necessary to develop the variables using traditional models or methods.|A step-by-step process was developed to guide small MPOs in the development of the base year and forecast year population, employment, household and income data needed to run TRIPCAL5, the trip generation model used by TxDOT in preparing the travel demand forecasts. Data sources as well as a recommended growth allocation process are included.

Report Number:



Demographic Forecasts, Population Projections, Employment Projections, Household Income Projections, Delphi, Trip Generation Data Inputs, Travel Demand Forecast Data

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