Systems and methods for determining quality measures for communication paths that can be used to conduct telephony communications determine and record quality measures for each of a plurality of paths during different times of the day and different days of the week. This information is used to determine and record measures of how the quality of each path varies over predetermined periods of time. When it is necessary to select a path for the setup of a new telephony communication, information regarding the anticipated quality of different potential paths, and information regarding how that quality is expected to vary over the duration of the telephony communication are used to select a path for the telephony communication.