Transit through an area by a population of travelers may be evaluated by a number of techniques, and may be useful for routing, transit time estimation, and transit control. Some techniques involve the use of probes, such as individuals or vehicles that are tagged and trackable through the area. However, estimating properties such as transit queue volume through probe counts may be difficult, as the ratio of probes to the overall population may vary. Presented herein are techniques for estimating transit properties by evaluating transit queues to estimate the probe ratio for an area. Such techniques involve counting and tracking the probes in a transit queue to estimate a queue length change of the transit queue, and a probe rate change of probes entering and exiting the transit queue. This information may inform estimates of the probe ratio, and in turn regional transit estimates, such as transit queue volumes.