Traffic signal installation requires considerable data collection and analysis. The MUTCD lists 9 warrants for the placement of traffic signals and can be found at https://mutcd.fhwa.dot.gov/pdfs/2009r1r2/part4.pdf. The fulfillment of a warrant or warrants does not in itself justify the installation of a signal. Installing a traffic signal at a low-volume intersection can significantly increase crashes and delays. Although traffic signals can reduce the total number of collisions at an intersection, research has shown that certain types of crashes (e.g., rear-end collisions) may actually increase after a signal is installed. For this reason, the type and number of crashes at an intersection should be considered before the installation of a signal. Traffic signals can represent a public investment when justified, and cost $150,000 to $250,000 to install.