While the amount of relief granted is at the Texas Transportation Commission’s discretion, the commission has not deviated from the adjustments recommended by TPP. TPP recommends adjustments based on a percentage formula developed by the Finance Division. The formula serves as a measure of a local government’s “effort” and “ability” to provide their local match for projects.

Cities within an economically disadvantaged county may receive higher percentage adjustments beyond their respective county’s adjustment under two conditions: if they have a local economic development sales tax and their population is less than 5000. A city within an economically disadvantaged county receives an adjustment equal to the adjustment for the county in which it is located, with the possibility of up to 10 additional percentage points based on its population and the existence of an economic development sales tax. An adjustment cannot exceed 95 percent in total (including percentage points for economic development sales tax) or be less than 15 percent.