Historical growth rates are developed by calculating traffic growth rates between past years at multiple locations within and near the study area. It is suggested that historical growth rates are developed for as many years as there is available data. It is suggested that regression analysis be performed on historical counts to determine an average linear growth rate. Historical growth factor is determined based on the average growth rate. Check traffic data to assess whether it is necessary to exclude any outlier data from the analysis and document accordingly. An example of the historical growth rate calculation is provided in

Appendix D, Section 4 – Regression Calculations

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