Greetings. I have a question regarding the heavy vehicle and grade adjustment factor for saturation flow rate at signalized intersections. Equations 19-9 and 19-10 are provided to calculate the HV/Grade factor for negative (downhill) and positive (uphill) grades, respectively. However, below these equations is a statement "This factor applies to heavy vehicle percentages up to 50% and grades ranging from -4.0% to +10.0%". My question is: what if you have an approach grade that is less than -4% or greater than 10%? There doesn't appear to be any guidance on how to handle steeper grades. Any insight or information that can be provided would be greatly appreciated. Thank you in advance.